The way users hold a smartphone depends on the interaction task, yet little is known about the fingers’ engagement with the device’s surfaces beyond the touchscreen. Such an understanding not only opens up opportunities for novel on- and off-screen interactions, but also the device’s possible physical affordances. We present a study (N=23) that examines the hands’ physical engagement with the smartphone beyond the touchscreen across nine mobile interactions. Grasps were annotated from photographs, and contact regions were captured using residual heat traces from grasping the device. Our findings show that fingers and palms adopt a variety of support roles and postures when engaging with the smartphone’s back and side edges. The hand-contact maps reveal distinct patterns, differing in contact frequency and placement. This work contributes an empirical characterisation of hands’ back and edge engagement, highlighting design opportunities for future smartphone usage extending beyond the touchscreen.

Mixed reality (MR) technologies are evolving to become more portable, incorporating video see-through capabilities, which enable a shift from stationary to mobile use. This development allows MR headsets to be used in various everyday contexts, including eating, travelling, and exercising. Before MR technologies reshape how we live and seamlessly integrate into our daily activities, we must understand the lived experiences of using MR in our personal lives and their influences and implications on our day-to-day activities. This paper presents an autoethnographic study that adopts an exploratory first-person perspective to uncover challenges and opportunities within this intimate context. We present the experiences and challenges of living in mixed reality, including on-the-go scenarios and social interactions. Our findings reveal issues such as social and ethical concerns and offer lessons learned to inform the design of future interactive systems for mobile mixed reality.

Assistive technologies (ATs) have the potential to empower blind and low vision (BLV) people. Yet, they often remain underutilised due to their immobility and limited applicability across scenarios. This paper presents LifeInsight, an AI-powered assistive wearable for BLV people that uses a wearable camera, microphone and single-click interface for goal-oriented visual querying. To inform the design of LifeInsight, we first collected a corpus of BLV people’s daily experiences using video probes and interviews. Ten BLV people recorded their daily experiences over one week using GoPro cameras, providing empirical insights. Based on these, we report on LifeInsight and its evaluation with 13 BLV people across six scenarios. LifeInsight effectively responded to visual queries, such as distinguishing between jars or identifying the status of a candle. Drawing on our work, we conclude with key lessons and practical recommendations to guide future research and advance the development and evaluation of AI-powered assistive wearables.

Giving citizens a voice in urban development processes is crucial for enabling socially sustainable cities and communities. However, citizens’ opportunities to express ideas are often limited to communication channels that offer poor incentives for participation. In this paper, we conducted an in-the-wild technology probe study (N=16) using a generative AI (GenAI) tool to allow citizens to visualise and submit urban development ideas by taking pictures and manipulating them with GenAI. The results highlight the potential of GenAI to empower, engage, and inspire citizens‘ creativity. We then conducted additional expert interviews (N=6) with city representatives and community associates. They voiced GenAI’s value in early-stage citizen participation but raised concerns about excluding senior citizens. Building on these insights, we present the design and evaluation (N=10) of UrbAI, a co-creative system tailored to urban development participation and conclude with lessons learned to inform how GenAI could be embedded in future citizen participation processes.

Mobile navigation applications are good at providing efficient navigation instructions. However, they currently lack the capability to facilitate free exploration. Therefore, users are limited to encountering only places close to the shortest paths, neglecting places that could diversify navigation and foster spatial learning. To better understand what characteristics places have that users like to explore we collected a dataset with a mobile application that encourages free exploration using gamification (n = 39, t = 455 days, 106.50 𝑘𝑚2). Using OpenStreetMap data, we found highly frequented freely explored places comprising office, educational, retail, touristic and commercial places. When comparing the characteristics of the freely explored places to those along the shortest path, those categories were different. Based on our findings, we propose that implementing more diverse routing algorithms can enhance navigation diversity, improve spatial learning, and optimise the utilisation of urban spaces for travel.

Negative emotions such as sadness or anger are often seen as something to be avoided. However, recognising, processing and regulating challenging emotional experiences can facilitate personal growth and is essential for long-term well-being. To support people in regulating and reflecting on negative emotions, we designed MoodShaper — a VR experience where participants autonomously create a virtual environment combined with emotion regulation (ER) interventions. Our system included three different interventions designed based on interviews with psychotherapists. We evaluated MoodShaper in a mixed-method between-subject study with n = 60 participants. Participants experienced one of the three ER interventions, allowing them to manipulate visual representations of negative emotions through externalisation, seclusion, or appreciation. We found that MoodShaper significantly increased positive affect while decreasing difficulties in ER and negative affect. Our work demonstrates how VR can provide technology-mediated support to reflect on, engage with and manage negative emotions. We contribute insights for future VR systems which support ER for challenging situations.

As foldable mobile devices grow in popularity, they often feature two screens—a smaller cover screen and a larger inside one, accessible by unfolding the device vertically or horizontally. Despite this, most mobile applications, including map apps, have yet to be fully optimised for these interfaces. This paper explores adaptations of mobile map applications for foldable mobile devices to enhance usability and user satisfaction. In a user study with nine participants, we identify key aspects of mobile map app design for exploration and navigation scenarios. Our results show that in navigation scenarios, screens should provide complementary information, with turn-by-turn instructions on one screen and a route overview on the other. Furthermore, our results show that map views should maintain map alignment and orientation across screens during exploration to prevent disorientation. Ultimately, we find that the success of mobile maps on foldable devices rests on the role and importance of context and user preference in mobile map interactions. Foldable devices offer a valuable chance of improving the mobile map experience on mobile devices if designers find useful ways to make use of the two screens and the increase screen real estate.

Online grocery shopping offers time-saving efficiency and convenience, yet many people still prefer physical shopping for trust in food freshness and other sensory experiences. While online stores are evolving to offer new user experiences, such as supporting eco-friendly or ethical shopping, the desktop and mobile platforms limit the engagement of such experiences. Virtual Reality (VR) presents an opportunity to create immersive and rich grocery shopping experiences, closing the gap between the convenience of online shopping and the sensory experience of physical shopping. Yet, designing VR grocery stores remains relatively unexplored. In this paper, we investigate the long-term potential of VR grocery stores, focusing on meeting individual needs. Through a co-design workshop, participants brainstormed the design of product displays, in-shop navigation, shopping carts, social shopping, among others. Based on our findings, we provide design recommendations for future VR grocery shopping to develop meaningful alternatives to existing shopping experiences for groceries.

Autoethnography is a valuable methodological approach bridging the gap between personal experiences and academic inquiry, enabling researchers to gain deep insights into various dimensions of technology use and design. While its adoption in Human-Computer Interaction (HCI) continues to grow, a comprehensive investigation of its function and role within HCI research is still lacking. This paper examines the evolving landscape of autoethnographies within HCI over the past two decades through a systematic literature review. We identify prevalent themes, methodologies, and contributions emerging from autoethnographies by analysing a corpus of 31 HCI publications. Furthermore, we detail data collection techniques and analysis methods and describe reporting standards. Our literature review aims to inform future (HCI) researchers, practitioners, and designers. It encourages them to embrace autoethnography’s rich opportunities by providing examples across domains (e.g., embodiment or health and wellbeing) to advance our understanding of the complex relationships between humans and technology.

Dedicated handheld controllers facilitate haptic experiences of virtual objects in mixed reality (MR). However, as mobile MR becomes more prevalent, we observe the emergence of controller-free MR interactions. To retain immersive haptic experiences, we explore the use of mobile devices as a substitute for specialised MR controller. In an exploratory gesture elicitation study (n = 18), we examined users’ (1) intuitive hand gestures performed with prospective mobile devices and (2) preferences for real-time haptic feedback when exploring haptic object properties. Our results reveal three haptic exploration modes for the mobile device, as an object, hand substitute, or as an additional tool, and emphasise the benefits of incorporating the device’s unique physical features into the object interaction. This work expands the design possibilities using mobile devices for tangible object interaction, guiding the future design of mobile devices for haptic MR experiences.

Virtual reality (VR) objects react dynamically to users’ touch interactions in real-time. However, experiencing changes in weight through the haptic sense remains challenging with consumer VR controllers due to their limited vibrotactile feedback. While prior works successfully applied pseudo-haptics to perceive absolute weight by manipulating the control-display (C/D) ratio, we continuously adjusted the C/D ratio to mimic weight changes. Vibrotactile feedback additionally emphasises the modulation in the virtual object’s physicality. In a study (N=18), we compared our multimodal technique with pseudo-haptics alone and a baseline condition to assess participants’ experiences of weight changes. Our findings demonstrate that participants perceived varying degrees of weight change when the C/D ratio was adjusted, validating its effectiveness for simulating dynamic weight in VR. However, the additional vibrotactile feedback did not improve weight change perception. This work extends the understanding of designing haptic experiences for lightweight VR systems by leveraging perceptual mechanisms.

Adolescence is a period of growth and exploration, marked by influential relationships with peers and parents. These relationships are essential for teenagers’ well-being, highlighting the need to support their interpersonal interactions. Emotional expression is key in resolving conflicts that can frequently arise. This paper investigates the potential of TeenWorlds, a Virtual Reality (VR) application, to facilitate emotional expression and shared understanding among teenagers and their peers and parents. In our study, teenagers, accompanied by either a peer or a parent (total n=42), used TeenWorlds to visually represent their emotions during a shared conflict, discuss them, and collaborate on a joint VR drawing. Our findings indicate that TeenWorlds can foster communication, reflection, and strengthen interpersonal relationships. However, notable differences were observed in interactions with peers versus parents. We contribute insights into designing VR systems that support reflective experiences and meaningful family interactions, ultimately enhancing the well-being of adolescents, parents, and families.

Whether it is sleep, diet, or procrastination, changing behaviours can be challenging. Individuals could design and build their own personalised digital interventions to help them reach their goals, but little is known about this process. Building upon previous research we propose the Behaviour Change with Trigger-Action Programming (BC-TAP) model which describes how individuals could bridge the gap between their current and desired behaviour through the creation of 'Do-It-Yourself' (DIY) digital interventions. We conducted a two-day participatory workshop based on the BC-TAP model with 28 participants. Participants articulated plans to change a behaviour of their choice and represented these plans in mobile device automations. After using their interventions for up to three weeks, participants reflected on their experience. Our findings report opportunities and challenges at each stage of the process. While formulating a digital proxy for certain behaviours was challenging, both failures and successes facilitated participants' awareness of their behaviour, and their ability to change it.

Playing together is crucial to the unique and invaluable bond between grandparents and grandchildren. However, co-located interactions and play can be limited due to time, distance, or pandemic-related restrictions. To facilitate distributed play, we developed MagiBricks, a system comprised of 3D-printed smart toy bricks and baseplates that provide feedback regarding their placement. The familiarity and appeal of toy bricks to both older adults and children make them ideal for intergenerational play. We conducted a within-subjects study with six grandparent-grandchildren pairs. We compared the interactions and perceived connectedness of the pairs while playing over a distance with either i) MagiBricks or ii) identical regular toy bricks. We found that MagiBricks affected communication dynamics, role taking, nature of play, and perception of connectedness during playtime compared to regular bricks, and were unanimously preferred. We contribute design implications for future systems leveraging (smart) tangibles and fostering intergenerational connectedness.

Getting from A to B has never been easier. Mobile navigation systems allow universal access to spatial information. However, following detailed route instructions leads to a decrease in spatial exploration behaviour and therefore a reduction of spatial knowledge acquisition. Facilitating spatial exploration has the potential to counteract this negative effect. This paper investigates how we can support people in re-discovering their surroundings. We designed and evaluated a mobile application to promote spatial exploration through gamification. The app requires active exploration behaviour to uncover a map. Gamification elements such as quests, statistics, and social competition are used to encourage exploration. We conducted an exploratory field study (n = 22). Our results show a significant increase in familiarity with the environment and a variety of exploration patterns. Based on our findings, we propose modifications to current mapping applications by limiting the visible cartographic elements and alternating routes to improve spatial knowledge acquisition.

Designing for children with ADHD has been of increasing interest to the HCI community. However, current approaches do not adequately involve all relevant stakeholders, and primarily focus on addressing symptoms, following a medical model of disability that is extrinsic to neurodivergent interests. To address this, we employed a multi-step, multi-stakeholder approach (N=31). First, we conducted 1) interviews with children with ADHD and their care ecosystem followed by 2) a co-design pilot with one child with ADHD and his therapists and an interview with a UX designer and an occupational therapist. We then employed 3) co-design sessions with neurotypical children and children with ADHD, and 4) a focus group with their therapists. We identified communication and reflection as key concepts for empowering and promoting the well-being of children with ADHD and their care ecosystem. We contribute design implications for future systems aiming to promote the overall well-being of this population.

More than 50 years after the last human set foot on the Moon during the Apollo 17 mission, humans aim to return to the Moon in this decade. This time, humanity plans to establish lunar habitats for a sustainable longer presence. An integrated part of these lunar habitats will be planetary surface greenhouses. These greenhouses will produce food, process air, recycle water, and improve the psychological well-being of humans. Past research has shown that a large amount of crew time, a scarce and valuable resource in spaceflight, is needed for maintenance and repairs in a planetary surface greenhouse, leaving less time for crop cultivation and science activities. In this paper, we present the concept of an augmented reality interface named ARCHIE2to reduce crew time and the workload of astronauts and remote support teams on Earth to operate a planetary surface greenhouse. ARCHIE2allows users to visualize status information on plants, technical systems, and environmental parameters in the greenhouse or other features supporting the greenhouse operations using an augmented reality headset. In particular, we report on the implementation and performance of the ARCHIE2plant detection module that runs locally on the augmented reality headset. Using images with a resolution of 320$\times$l92 pixels, arugula selvatica plants were detected using an artificial neural network (based on a YOLOv5s model) from a horizontal distance up to 50 cm with an average inference time of 602 ms and an average of 48 FPS. Based on that, the plants were augmented with labels to visualize relevant plant-specific information supporting astronauts in the maintenance of the plants.

System administrators (sysadmins) are key to keeping computer networks safe. As networks grow in size and complexity, partial workflow automation with the help of AI has been introduced to assist them. However, AI-aided tools often lack transparency, which may lead to the sysadmin’s reluctance to use the new software, slower response time in case of a security breach, and increasing errors. Related work suggests that the concept of social transparency (ST), when applied to the IT-security context, enables peer support and could provide the missing knowledge to the user facilitating explainability of the system and improving human-AI trust. In this paper, we investigate the profile of sysadmins and confirm that ST can indeed yield benefits for them but only when coupled with relevant contextual information and only when it adheres to the sysadmins’ quality standards. Finally, we contribute design recommendations for incorporating ST into the existing workflows of sysadmins.

Handheld virtual reality (VR) controllers enable users to manipulate virtual objects in VR but do not convey a virtual object's weight. This hinders users from effectively experiencing lighter and heavier objects. While previous work explored either hardware-based interfaces or software-based pseudo-haptics, in this paper, we combine two techniques to improve the virtual weight perception in VR. By adapting the trigger resistance of the VR controller when grasping a virtual object and manipulating the control-display (C/D) ratio during lifting, we create a continuous weight sensation. In a psychophysical study (N=29), we compared our combined approach against the individual rendering techniques. Our results show that participants were significantly more sensitive towards smaller weight differences in the combined weight simulations compared to the individual methods. Additionally, participants were also able to determine weight differences significantly faster with both cues present compared to the single pseudo-haptic technique. While all three techniques were generally valued to be effective, the combined approach was favoured the most. Our findings demonstrate the meaningful benefit of combining physical and virtual techniques for virtual weight rendering over previously proposed methods.

We have witnessed astonishing progress in mobile and ubiquitous technology in the past two decades. Our interaction-supporting devices have become increasingly capable and diverse, while the supporting infrastructure, including heterogeneous networks and cloud computing, has matured to enable our vision of a ubiquitous computing environment. As we navigate this new frontier, we find ourselves pondering the words of Bill Buxton: "Now that we can do anything, what should we do?" and, more importantly, "How should it work?" Buxton's thought-provoking statement urges us to shift our focus towards methodological considerations and, crucially, ethics. The MobileHCI community, as a whole, recognizes the importance of ethical practices in shaping our field. While our work has often touched upon privacy-maintaining interactions and service provision, it is time to delve deeper into the ethical dimensions of our research and design choices.

This paper presents a systematic review of HCI literature focusing on children with ADHD, the prevailing mental health diagnosis in children. Its aim is to (i) chart the state-of-the-art in this domain (e.g. methods used), (ii) identify the ways the HCI community has addressed the needs of children with ADHD (e.g. technologies deployed), and (iii) describe the involvement of the various stakeholders playing a role in their everyday experiences (i.e. their care ecosystem). Our findings show limited engagement of the care ecosystem in the design, development and user studies of current technologies, and shortcomings in designing for multiple ecosystem stakeholders, despite their crucial role. We also find that most HCI contributions are systems aiming to address ADHD-related symptoms. Based on our findings, we provide suggestions for further research and design considerations for future systems that empower and promote the well-being of children with ADHD, while considering their care ecosystem.

Immersive interactive technologies such as virtual reality (VR) have the potential to foster well-being. While VR applications have been successfully used to evoke positive emotions through the presetting of light, colour and scenery, the experiential potential of allowing users to independently create a virtual environment (VE) has not yet been sufficiently addressed. To that end, we explore how the autonomous design of a VE can affect emotional engagement and well-being. We present Mood Worlds – a VR application allowing users to visualise their emotions by self-creating a VE. In an exploratory evaluation (N=16), we found that Mood Worlds is an effective tool supporting emotional engagement. Additionally, we found that an autonomous creation process in VR increases positive emotions and well-being. Our work shows that VR can be an effective tool to visualise emotions, thereby increasing positive affect. We discuss opportunities and design requirements for VR as positive technology.

Virtual Reality (VR) is increasingly being used to promote mindfulness practice. However, the impact of virtual and multimodal interactive spaces on mindfulness practice and presence is still underexplored. To address this gap, we conducted a mixed-method user study (N=12). We explored the impact of various multimodal feedback, in particular tactile feedback (passive haptic feedback by artificial grass) and auditory feedback (footstep sound) at feet level on both mindfulness and presence. We conducted semi-structured interviews and collected quantitative data through three validated questionnaires (SMS, IPQ, WSPQ). We found a significant effect of passive haptic feedback on presence and mindfulness. Tactile feedback improves the focus on the self, facilitates spatial presence and increases involvement. Auditory feedback did not significantly affect presence or mindfulness. While ambient sound was perceived as beneficial for presence, footstep sound subjectively disrupted both presence and mindfulness. Based on our results, we derive design recommendations for multimodal VR applications supporting mindfulness practice.

As-the-crow-flies (ATCF) navigation is an alternative to turn-by-turn navigation for cyclists utilizing the least-angle strategy by providing the beeline to the destination. However, past research found weaknesses (e.g., running into dead ends) affecting the user experience. In this paper, we investigate how the street network attributes to the experience of the navigation method. Using a feature importance analysis and comparison of different city types across 1633 cities, we analyze how ATCF navigation fits different environments. The perfect ACTF-city has long streets, many options to turn at decision points, few dead ends, and a grid-like structure. Cities well suited are primarily found in East Asia and North America. Furthermore, we find that previous ATCF studies were most likely conducted in Western Europe, which features the least suited street networks for the navigation method. We present design implications for future ATCF implementations and argue for diverse study locations in future research.

Privacy Policies inform users about how their personal data is managed while fulfilling the obligatory requirements. Past studies have shown that users often do not read privacy policies, cannot comprehend the long and complex policy documents, and resort to providing their consent without knowledge. To enable users to make an informed decision, we explored serious games as a new medium to improve their understanding of privacy policies. In a mobile escape room game, users engage with the data collection and processing by solving different puzzles. We validated the game concept in a user study by comparing it to a conventional textual policy. Our findings show that the game promoted greater information recall in users. However, a trade-off seems to exist between frustration, duration and understanding. We show strategies for turning a privacy policy into game elements for a mobile escape room game and incorporating privacy information into different puzzles. We recommend that the choice of a privacy policy format should vary in a case-by-case scenario and should accommodate different target audiences.

Abstract In this paper, we present a systematic analysis of large-scale human mobility patterns obtained from a passive Wi-Fi tracking system, deployed across different location typologies. We have deployed a system to cover urban areas served by public transportation systems as well as very isolated and rural areas. Over 4 years, we collected 572 million data points from a total of 82 routers covering an area of 2.8 km2. In this paper we provide a systematic analysis of the data and discuss how our low-cost approach can be used to help communities and policymakers to make decisions to improve people’s mobility at high temporal and spatial resolution by inferring presence characteristics against several sources of ground truth. Also, we present an automatic classification technique that can identify location types based on collected data.

Augmented reality applications allow users to enrich their real surroundings with additional digital content. However, due to the limited field of view of augmented reality devices, it can sometimes be difficult to become aware of newly emerging information inside or outside the field of view. Typical visual conflicts like clutter and occlusion of augmentations occur and can be further aggravated especially in the context of dense information spaces. In this article, we evaluate how multisensory cue combinations can improve the awareness for moving out-of-view objects in narrow field of view augmented reality displays. We distinguish between proximity and transition cues in either visual, auditory or tactile manner. Proximity cues are intended to enhance spatial awareness of approaching out-of-view objects while transition cues inform the user that the object just entered the field of view. In study 1, user preference was determined for 6 different cue combinations via forced-choice decisions. In study 2, the 3 most preferred modes were then evaluated with respect to performance and awareness measures in a divided attention reaction task. Both studies were conducted under varying noise levels. We show that on average the Visual-Tactile combination leads to 63% and Audio-Tactile to 65% faster reactions to incoming out-of-view augmentations than their Visual-Audio counterpart, indicating a high usefulness of tactile transition cues. We further show a detrimental effect of visual and audio noise on performance when feedback included visual proximity cues. Based on these results, we make recommendations to determine which cue combination is appropriate for which application.

With the rise of COVID-19 cases globally, many countries released digital tools to mitigate the effects of the pandemic. In Germany the Robert Koch Institute (RKI) published the Corona-Data-Donation-App, a virtual citizen science (VCS) project, to establish an early warning system for the prediction of potential COVID-19 hotspots using data from wearable devices. While work on motivation for VCS projects in HCI often presents egoistic motives as prevailing, there is little research on such motives in crises situations. In this paper, we explore the socio-psychological processes and motivations to share personal data during a pandemic. Our findings indicate that collective motives dominated among app reviews (n=464) and in in-depth interviews (n=10). We contribute implications for future VCS tools in times of crises that highlight the importance of communication, transparency and responsibility.

Interactive technologies are getting closer to our bodies and permeate the infrastructure of our homes. While such technologies offer many benefits, they can also cause an initial feeling of unease in users. It is important for Human-Computer Interaction to manage first impressions and avoid designing technologies that appear creepy. To that end, we developed the Perceived Creepiness of Technology Scale (PCTS), which measures how creepy a technology appears to a user in an initial encounter with a new artefact. The scale was developed based on past work on creepiness and a set of ten focus groups conducted with users from diverse backgrounds. We followed a structured process of analytically developing and validating the scale. The PCTS is designed to enable designers and researchers to quickly compare interactive technologies and ensure that they do not design technologies that produce initial feelings of creepiness in users.

Cycling is on the rise as a relevant alternative to car-based mobility and even though there are mobile applications specifically designed for cyclists to support this development, many still face unresolved challenges in terms of safe user interaction with complex data while riding. We present the design, development, and evaluation of VeloCity - an application for reporting traffic incidents and structures relevant to cyclists. In a case study, we compared its' three input methods (touch, in-app speech recognition, the voice assistant of the operating system) to evaluate which attributes make for safe interaction while cycling. We found that participants prefer to use the voice assistant over the other modalities as it was least distracting due to its hands- and eyes-free interaction design. Furthermore, they chose short commands over conversational phrases. Based on our results, we present five guidelines for designing voice user interfaces for cyclists and argue for moving away from touch-based interfaces in this domain, which still make up most of the applied interaction techniques today.

Long-term space missions are challenging and demanding for astronauts. Confined spaces and long-duration sensory deprivation may cause psychological problems for the astronauts. In this paper, we envision how extraterrestrial habitats (e.g., a habitat on the Moon or Mars) can maintain the well-being of the crews by augmenting the astronauts. In particular, we report on the design, implementation, and evaluation of conversational user interfaces (CUIs) for extraterrestrial habitats. The goal of such CUIs is to support scientists during their daily and scientific routines on their missions within the extraterrestrial habitat and provide emotional support. During a week-long so-called analog mission with four scientists using a Wizard of Oz prototype, we derived design guidelines for such CUIs. Successively, based on the derived guidelines, we present the implementation and evaluation of two CUIs named CASSIOPEIA and PEGASUS.

Millions of people use mobile map applications like Google Maps on a regular basis. However, despite these applications' ubiquity, the literature contains very little information about how these applications are used in the real world. As such, many researchers and practitioners seeking to improve mobile map applications may not be able to identify important challenges and may miss major opportunities for innovation. To address this paucity of usage information, we collected and analysed data during unsupervised usage of Google Maps by replacing the standard application with a wrapped version called MapRecorder. In two studies we recorded data from locals and tourists using our application and collected over 580 minutes of actual application usage from 34 users, spanning 555 unique sessions. We identify typical usage scenarios, observe a large amount of map exploration and elucidate generalisable interaction patterns.

Medical images taken with mobile phones by patients, i.e. medical selfies, allow screening, monitoring and diagnosis of skin lesions. While mobile teledermatology can provide good diagnostic accuracy for skin tumours, there is little research about emotional and physical aspects when taking medical selfies of body parts. We conducted a survey with 100 participants and a qualitative study with twelve participants, in which they took images of eight body parts including intimate areas. Participants had difficulties taking medical selfies of their shoulder blades and buttocks. For the genitals, they prefer to visit a doctor rather than sending images. Taking the images triggered privacy concerns, memories of past experiences with body parts and raised awareness of the bodily medical state. We present recommendations for the design of mobile apps to address the usability and emotional impacts of taking medical selfies.

Visual as-the-crow-flies (ATCF) navigation methods are an increasingly popular alternative to existing turn-by-turn (TBT) navigation for cyclists. To better understand how people use them in everyday navigation and how they cope with the novel navigation method in challenging situations, we studied two main issues posed by ATCF navigation: knowing whether one is on the right route to their destination and knowing whether a turn leads into a dead end or detour. To investigate these two problems, we compared visual ATCF navigation against (1) TBT navigation and (2) an improved ATCF+ navigation system in two successive studies. We found that users encountered problems riding in the opposite direction to the destination and were often turning around as a result using the ATCF method. Using colour cues in the ATCF user interface we were able to reinforce correct route choices. Additionally, we found that unsuccessful route progression negatively correlates with user confidence.

Passwords commonly contain personal information. However, there is limited awareness about its detrimental effect on the user’s online security. Current password meters do not take into account personal information and, therefore, their users are susceptible to targeted password guessing. In this paper, we present the MoiPrivacy password meter, that extends a neural network- and heuristic-based approach and considers a user’s personal information, while calculating the password strength and feedback. To do so, we analyzed the type of personal information used in passwords through an online survey (n = 62). We conducted a second user study (n = 49) for evaluating the MoiPrivacy browser extension. Our results show that MoiPrivacy significantly limits the inclusion of personal information in passwords.

Virtual realities (VR) are becoming an integral part of product development across many industries, for example to assess aesthetics and usability of new features in the automotive industry. The recording of the evaluation is typically conducted by filling out questionnaires after the study participants left the virtual environment. In this paper, we investigate how questionnaires can be best embedded within the virtual environment and compare how VR-questionnaires differ from classical post-test evaluations regarding preference, presence, and questionnaire completion time.

Current augmented reality displays still have a very limited field of view compared to the human vision. In order to localize out-of-view objects, researchers have predominantly explored visual guidance approaches to visualize information in the limited (in-view) screen space. Unfortunately, visual conflicts like cluttering or occlusion of information often arise, which can lead to search performance issues and a decreased awareness about the physical environment. In this paper, we compare an innovative non-visual guidance approach based on audio-tactile cues with the state-of-the-art visual guidance technique EyeSee360 for localizing out-of-view objects in augmented reality displays with limited field of view. In our user study, we evaluate both guidance methods in terms of search performance and situation awareness. We show that although audio-tactile guidance is generally slower than the well-performing EyeSee360 in terms of search times, it is on a par regarding the hit rate. Even more so, the audio-tactile method provides a significant improvement in situation awareness compared to the visual approach.

Dealing with fear of falling is a challenge in sport climbing. Virtual reality (VR) research suggests that using physical and reality-based interaction increases the presence in VR. In this paper, we present a study that investigates the influence of physical props on presence, stress and anxiety in a VR climbing environment involving whole body movement. To help climbers overcoming fear of falling, we compared three different conditions: Climbing in reality at 10 m height, physical climbing in VR (with props attached to the climbing wall) and virtual climbing in VR using game controllers. From subjective reports and biosignals, our results show that climbing with props in VR increases the anxiety and sense of realism in VR for sport climbing. This suggests that VR in combination with physical props are an effective simulation setup to induce the sense of height.

Mobile navigation apps are among the most used mobile applications and are often used as a baseline to evaluate new mobile navigation technologies in field studies. As field studies often introduce external factors that are hard to control for, we investigate how pedestrian navigation methods can be evaluated in virtual reality (VR). We present a study comparing navigation methods in real life (RL) and VR to evaluate if VR environments are a viable alternative to RL environments when it comes to testing these. In a series of studies, participants navigated a real and a virtual environment using a paper map and a navigation app on a smartphone. We measured the differences in navigation performance, task load and spatial knowledge acquisition between RL and VR. From these we formulate guidelines for the improvement of pedestrian navigation systems in VR like improved legibility for small screen devices. We furthermore discuss appropriate low-cost and low-space VR-locomotion techniques and discuss more controllable locomotion techniques.

Abstract This paper explores ‘A to B’ routing tools designed to chart accessible routes for wheelchair users. We develop and present a novel measurement framework based upon cost-benefit analysis in order to evaluate the real-world utility of routing systems for wheelchair users. Using this framework, we compare proposed routes generated by accessibility tools with the pedestrian routes generated by Google Maps by means of conducting expert assessments of the situation on the ground. Relative to tools aimed at pedestrians, we find that these tools are not significantly more likely to produce an accessible route, and more often than not, they present longer routes that arise from imaginary barriers that do not exist in the real world. This analysis indicates how future routing tools for wheelchair users should be designed to ensure that they genuinely ameliorate the effects of accessibility barriers in the built environment.

In this paper, we present OORT, a cooling system for head-mounted displays (HMDs) that improves wearing comfort by decreasing skin temperatures of the facial areas covered by the headset. The integrated cooling system consists of an electronically controlled fan blower. The fan compartment is integrated into an hmd padding element with custom-designed air flow channels that provide cool air circulation around the covered facial regions. We report on the design and implementation of OORT as a viable way to provide thermal comfort during long-term virtual reality experiences.

This paper investigates bias in coverage between Western and Arab media on Twitter after the November 2015 Beirut and Paris terror attacks. Using two Twitter datasets covering each attack, we investigate how Western and Arab media differed in coverage bias, sympathy bias, and resulting information propagation. We crowdsourced sympathy and sentiment labels for 2,390 tweets across four languages (English, Arabic, French, German), built a regression model to characterize sympathy, and thereafter trained a deep convolutional neural network to predict sympathy. Key findings show: (a) both events were disproportionately covered (b) Western media exhibited less sympathy, where each media coverage was more sympathetic towards the country affected in their respective region (c) Sympathy predictions supported ground truth analysis that Western media was less sympathetic than Arab media (d) Sympathetic tweets do not spread any further. We discuss our results in light of global news flow, Twitter affordances, and public perception impact.

As humans, we have the natural capability of localizing the origin of sounds. Spatial audio rendering leverages this skill by applying special filters to recorded audio to create the impression that a sound emanates from a certain position in the physical space. A main application for spatial audio on mobile devices is to provide non-visual navigation cues. Current systems require users to either listen to artificial beacon sounds, or the entire audio source (e.g., a song) is repositioned in space, which impacts the listening experience. We present NavigaTone, a system that takes advantage of multi-track recordings and provides directional cues by moving a single track in the auditory space. While minimizing the impact of the navigation component on the listening experience, a user study showed that participants could localize sources as good as with stereo panning while the listening experience was rated to be closer to common music listening.

Many applications of geotagged content are predicated on the concept of localness (e.g., local restaurant recommendation, mining social media for local perspectives on an issue). However, definitions of who is a "local" in a given area are typically informal and ad-hoc and, as a result, approaches for localness assessment that have been used in the past have not been formally validated. In this paper, we begin the process of addressing these gaps in the literature. Specifically, we (1) formalize definitions of "local" using themes identified in a 30-paper literature review, (2) develop the first ground truth localness dataset consisting of 132 Twitter users and 58,945 place-tagged tweets, and (3) use this dataset to evaluate existing localness assessment approaches. Our results provide important methodological guidance to the large body of research and practice that depends on the concept of localness and suggest means by which localness assessment can be improved.

Platforms like Google Maps or Bing Maps are used by a large number of users to find the shortest path to their destinations. While these services mainly focus on supporting drivers and pedestrians, first services exist that support wheelchair users. Routing algorithms for wheelchair users try to avoid obstacles like stairs or bollards and optimize on criteria like surface properties and slope of the route. In this study, we undertake the first controlled examination of wheelchair routing approaches. By analyzing three routing platforms, including two wheelchair routing algorithms and three pedestrian routing algorithms, across fifteen major cities in Germany, our results highlight that the routes for wheelchair users are significantly longer and partially also more complex than those for pedestrians. In addition, we show that today's pedestrian routing algorithms also output very diverse routes.

In presence of conflicting or ambiguous visual cues in complex scenes, performing 3D selection and manipulation tasks can be challenging. To improve motor planning and coordination, we explore audio-tactile cues to inform the user about the presence of objects in hand proximity, e.g., to avoid unwanted object penetrations. We do so through a novel glove-based tactile interface, enhanced by audio cues. Through two user studies, we illustrate that proximity guidance cues improve spatial awareness, hand motions, and collision avoidance behaviors, and show how proximity cues in combination with collision and friction cues can significantly improve performance.

We present a novel forearm-and-glove tactile interface that can enhance 3D interaction by guiding hand motor planning and coordination. In particular, we aim to improve hand motion and pose actions related to selection and manipulation tasks. Through our user studies, we illustrate how tactile patterns can guide the user, by triggering hand pose and motion changes, for example to grasp (select) and manipulate (move) an object. We discuss the potential and limitations of the interface, and outline future work.

The widespread popularity of Pokémon GO presents the first opportunity to observe the geographic effects of location-based gaming at scale. This paper reports the results of a mixed methods study of the geography of Pokémon GO that includes a five-country field survey of 375 Pokémon GO players and a large scale geostatistical analysis of game elements. Focusing on the key geographic themes of places and movement, we find that the design of Pokémon GO reinforces existing geographically-linked biases (e.g. the game advantages urban areas and neighborhoods with smaller minority populations), that Pokémon GO may have instigated a relatively rare large-scale shift in global human mobility patterns, and that Pokémon GO has geographically-linked safety risks, but not those typically emphasized by the media. Our results point to geographic design implications for future systems in this space such as a means through which the geographic biases present in Pokémon GO may be counteracted.

Much research has shown that social media platforms have substantial population biases. However, very little is known about how these population biases affect the many algorithms that rely on social media data. Focusing on the case study of geolocation inference algorithms and their performance across the urban-rural spectrum, we establish that these algorithms exhibit significantly worse performance for underrepresented populations (i.e. rural users). We further establish that this finding is robust across both text- and network-based algorithm designs. However, we also show that some of this bias can be attributed to the design of algorithms themselves rather than population biases in the underlying data sources. For instance, in some cases, algorithms perform badly for rural users even when we substantially overcorrect for population biases by training exclusively on rural data. We discuss the implications of our findings for the design and study of social media-based algorithms.

Catastrophic incidents associated with GPS devices and other personal navigation technologies are sufficiently common that these incidents have been given a colloquial nickname: "Death by GPS". While there is a significant body of work on the use of personal navigation technologies in everyday scenarios, no research has examined these technologies' roles in catastrophic incidents. In this paper, we seek to address this gap in the literature. Borrowing techniques from public health research and communication studies, we construct a corpus of 158 detailed news reports of unique catastrophic incidents associated with personal navigation technologies. We then identify key themes in these incidents and the roles that navigation technologies played in them, e.g. missing road characteristics data contributed to over 25% of these incidents. With the goal of reducing casualties associated with personal navigation technologies, we outline implications for design and research that emerge from our results, e.g. advancing "space usage rule" mapping, incorporating weather information in routing, and improving visual and audio instructions in complex situations.

The financial crisis and austerity politics in Europe has had a devastating impact on public services, social security and vulnerable populations. Greek civil society responded quickly by establishing solidarity structures aimed at helping vulnerable citizens to meet their basic needs and empower them to co-create an anti-austerity movement. While digital technology and social media played an important role in the initiation of the movement, it has a negligible role in the movement's on-going practices. Through embedded work with several solidarity structures in Greece, we have begun to understand the "solidarity economy" (SE) as an experiment in direct democracy and self-organization. Working with a range of solidarity structures we are developing a vision for a "Solidarity HCI" committed to designing to support personal, social and institutional transformation through processes of agonistic pluralism and contestation, where the aims and objectives of the SE are continuously re-formulated and put into practice.

We introduce WatchThru, an interactive method for extended wrist-worn display on commercially-available smartwatches. To address the limited visual and interaction space, WatchThru expands the device into 3D through a transparent display. This enables novel interactions that leverage and extend smartwatch glanceability. We describe three novel interaction techniques, Pop-up Visuals, Second Perspective and Peek-through, and discuss how they can complement interaction on current devices. We also describe two types of prototypes that helped us to explore standalone interactions, as well as, proof-of-concept AR interfaces using our platform.

Many destinations' economies strongly rely on tourism. Therefore, it is crucial to meet tourists' expectations, so they will return to the destination. The geographical formation of certain touristic islands often leads to local climates where it can be rainy and windy on one side of the island, whereas the other part is sunny. In this paper, we present a novel use for a network of sensors, LightBeam, a mobile location-based application aiming to improve the tourists' experience. The application focuses on providing real-time guidance for tourists seeking sunlight to maximize their holiday experience by suggesting the closest points of interest (POIs) to the user with the "best sunlight". To achieve this, we implemented and installed a network of geospatial sensors. The data from the sensor network is combined with the current location of the users to provide recommendations. We report on the initial design and prototype of LightBeam.

Being in nature is typically regarded to be calming, relaxing and purifying. When in nature, people often seek to be mobile through physical activity such as hiking. But also, nature provides an opportunity for meditative, mindful or inspiring experiences remote from urban everyday life. Mobile Technologies such as sports tracking technologies, electronic tourist guides, mobile phone integrated cameras and omnipresent social media access, have potential to both enhance and disrupt a user's interaction with and experience of nature. This MobileHCI workshop follows on from the first successful NatureCHI workshop by focusing on the challenges associated with the design of mobile technologies that support unobtrusive interaction in nature.

Landmark-based navigation systems have proven benefits relative to traditional turn-by-turn systems that use street names and distances. However, one obstacle to the implementation of landmark-based navigation systems is the complex challenge of selecting salient local landmarks at each decision point for each user. In this paper, we present Pharos, a novel system that extends turn-by-turn navigation instructions using a single global landmark (e.g. the Eiffel Tower, the Burj Khalifa, municipal TV towers) rather than multiple, hard-to-select local landmarks. We first show that our approach is feasible in a large number of cities around the world through the use of computer vision to select global landmarks. We then present the results of a study demonstrating that by including global landmarks in navigation instructions, users navigate more confidently and build a more accurate mental map of the navigated area than using turn-by-turn instructions.

360° videos are a new kind of medium that gives the viewers a sense of real immersion as they glimpse the action from all angles and directions. Naturally, professional and amateur film-makers are actively adopting this new medium for transformative storytelling. Despite this phenomenal progress in 360° video creation, current understanding on users' viewing experience of these videos is limited. In this paper, we present the first comparative study on the user experience with 360° videos on mobile devices using different interaction techniques. We observed 18 participants' interaction with six 360°videos with different viewport characteristics (static or moving) on a smartphone, a tablet and a head mounted display (HMD) respectively and measured how they interact with the content. We then conducted semi-structured interviews with the participants in which they explained their interaction with and viewing experience of 360° videos across three devices. Our findings show that 360° videos with moving viewports elicit higher engagement from the viewers, and offer superior viewing experience. However, these videos are cognitively demanding and require constant user attention. Our participants preferred the condition with dynamic peephole interaction on a smartphone for watching 360° videos due to the simplicity in exploration and familiarity with navigation controls. Many participants reported that the HMD offers the most immersive experience however it comes at the expense of higher cognitive burden, motion sickness and physical discomfort.

While popular digital maps support an unprecedented number of use cases, new reference map customization tools have been created for purposes for which those maps fall short. With the goal of informing the design of this new class of cartographic tools, we present the first study of naturalistic ("bespoke") map customization behavior. Through a mixed methods and mixed-media approach involving a survey, the analysis of a corpus of customized maps, and an interview with a power user, we find that bespoke map customization is a relatively common activity and identify frequent use cases as well as map customization strategies. We discuss these use cases and strategies in detail, and propose design implications for future customization tools, such as the use of templates for common use cases, adaptability for various customization styles and the support of multimedia interaction.

Choosing a seat for traveling can be a complex evaluation of constraints depending on personal preferences. There are websites that help to choose the best seat in a bus, in a train, or on an airplane. However, these recommendations only consider seat-related factors and not the view from the window. While a scenic view rarely influences the decision for a seat on a plane, it is much more important for train rides and especially for scenic bus tours. Therefore, travel website users often discuss which side offers the best view on a specific trip. We propose an algorithm, which decides on which side of the road the view is the most scenic based on Google Street View images. These results can be used by travelers to choose a seat and by scenic tour providers to balance the scenic views between sides or add options during checkout.

Many virtual and mixed reality games focus on single player experiences. In this paper, we describe the concept and prototype implementation of a mixed reality multiplayer game that can be played with a smartphone and an HMD in outdoor environments. Players can team up to fight against attacking alien drones. The relative positions between the players are tracked using GPS, and the rear camera of the smartphone is used to augment the environment and teammates with virtual objects. The combination of multiplayer, mixed reality, the use of geographical location and outdoor action together with affordable, mobile equipment enables a novel strategic and social game experience.

An increasing share of our daily interactions with others is mediated through mobile communication technologies. People communicate via text, emoticons, emojis and rich media such as video. We explore the design of Heartefacts, short video clips composed of highlights determined by heart rate changes while watching videos. Our survey investigated video sharing behaviour, and our feasibility study examined the possibility of detecting highlights in videos by monitoring people's heart rates measured with off-the-shelf wrist-worn sensors. Our results show that people do indeed have measurable responses with respect to their heartbeat patterns to six different emotions elicited by video clips. We compare video highlights verbally identified by our participants to physiological highlights as indicated by their heart rate data and also discuss and compare the automatically generated Heartefacts with video highlights created by an expert in video art. We close with design considerations for Heartefacts in mobile technology.

Wikipedia articles about places, OpenStreetMap features, and other forms of peer-produced content have become critical sources of geographic knowledge for humans and intelligent technologies. In this paper, we explore the effectiveness of the peer production model across the rural/urban divide, a divide that has been shown to be an important factor in many online social systems. We find that in both Wikipedia and OpenStreetMap, peer-produced content about rural areas is of systematically lower quality, is less likely to have been produced by contributors who focus on the local area, and is more likely to have been generated by automated software agents (i.e. "bots"). We then codify the systemic challenges inherent to characterizing rural phenomena through peer production and discuss potential solutions.

Geotagged tweets and other forms of social media volunteered geographic information (VGI) are becoming increasingly critical to many applications and scientific studies. An important assumption underlying much of this research is that social media VGI is "local", or that its geotags correspond closely with the general home locations of its contributors. We demonstrate through a study on three separate social media communities (Twitter, Flickr, Swarm) that this localness assumption holds in only about 75% of cases. In addition, we show that the geographic contours of localness follow important sociodemographic trends, with social media in, for instance, rural areas and older areas, being substantially less local in character (when controlling for other demographics). We demonstrate through a case study that failure to account for non-local social media VGI can lead to misrepresentative results in social media VGI-based studies. Finally, we compare the methods for determining localness, finding substantial disagreement in certain cases, and highlight new best practices for social media VGI-based studies and systems.

The lack of certain types of geographic data prevents the development of location-aware technologies in a number of important domains. One such type of "unmapped" geographic data is space usage rules (SURs), which are defined as geographically-bound activity restrictions (e.g. "no dogs", "no smoking", "no fishing", "no skateboarding"). Researchers in the area of human-computer interaction have recently begun to develop techniques for the automated mapping of SURs with the aim of supporting activity planning systems (e.g. one-touch "Can I Smoke Here?" apps, SUR-aware vacation planning tools). In this paper, we present a novel SUR mapping technique -- SPtP -- that outperforms state-of-the-art approaches by 30% for one of the most important components of the SUR mapping pipeline: associating a point observation of a SUR (e.g. a 'no smoking' sign) with the corresponding polygon in which the SUR applies (e.g. the nearby park or the entire campus on which the sign is located). This paper also contributes a series of new SUR benchmark datasets to help further research in this area.

Navigation systems allow drivers to find the shortest or fastest path between two or multiple locations mostly using time or distance as input parameters. Various researchers extended traditional route planning approaches by taking into account the user's preferences, such as enjoying a coastal view or alpine landscapes during a drive. Current approaches mainly rely on volunteered geographic information (VGI), such as point of interest (POI) data from OpenStreetMap, or social media data, such as geotagged photos from Flickr, to generate scenic routes. While these approaches use proximity, distribution or other spatial relationships of the data sets, they do not take into account the actual view on specific route segments. In this paper, we propose Autobahn: a system for generating scenic routes using Google Street View images to classify route segments based on their visual characteristics enhancing the driving experience. We show that this vision-based approach can complement other approaches for scenic route planning and introduce a personalized scenic route by aligning the characteristics of the route to the preferences of the user.

Mobile devices are currently the most commonly used platform to experience Augmented Reality (AR). Nevertheless, they typically provide a less than ideal ergonomic experience, requiring the user to operate them with arms raised. In this paper we evaluate how to improve the ergonomics of AR experiences by modifying the angle between the mobile device's camera and its display. Whereas current mobile device cameras point out vertically from the back cover, we modify the camera angle to be 0, 45 and 90 degrees. In addition, we also investigate the use of the smartwatch as an AR browser form factor. Key findings are, that whilst the current approximately see-through configuration provides the fastest task completion times, a camera offset angle of 45° provides reduced task load and was preferred by users. When comparing different form factors and screen sizes, the smartwatch format was found to be unsuitable for AR browsing use.

Providing pedestrian navigation instructions on small screens is a challenging task due to limited screen space. As image-based approaches for navigation have been successfully proven to outperform map-based navigation on mobile devices, we propose to bring image-based navigation to smartwatches. We contribute a straightforward pipeline to easily create image-based indoor navigation instructions that allow users to freely navigate in indoor environments without any localization infrastructure and with minimal user input on the smartwatch. In a user study, we show that our approach outperforms the current state-of-the art application in terms of task completion time, perceived task load and perceived usability. In addition, we did not find an indication that there is a need to provide explicit directional instructions for image-based navigation on small screens.

In this workshop, we will review and discuss open issues, technical challenges and conceptual models for multi-device spatial or proxemic interaction. We aim to bring together researchers, students and practitioners working on technical infrastructures, studies and designs of spatial in-terfaces, or domain specific multi-device applications that use space as a unit of analysis. We focus specifically on analysing how such interfaces, tools and tracking technolo-gy can be deployed "in the wild". The workshop will facili-tate knowledge exchange about the current state of spatial and proxemic interactive systems, identify application do-mains and enabling technologies for cross-surface interac-tions in the wild, and establish a research community to develop effective strategies for successful design of cross-device interactions.

Nonverbal and unconscious behaviour is an important component of daily human-human interaction. This is especially true in situations such as public speaking, job interviews or information sensitive conversations, where researchers have shown that an increased awareness of one's behaviour can improve the outcome of the interaction. With wearable technology, such as Google Glass, we now have the opportunity to augment social interactions and provide realtime feedback on one's behaviour in an unobtrusive way. In this paper we present Logue, a system that provides realtime feedback on the presenters' openness, body energy and speech rate during public speaking. The system analyses the user's nonverbal behaviour using social signal processing techniques and gives visual feedback on a head-mounted display. We conducted two user studies with a staged and a real presentation scenario which yielded that Logue's feedback was perceived helpful and had a positive impact on the speaker's performance.

Recent work has identified the lack of space usage rule (SUR) data -- e.g. "no smoking", "no campfires" -- as an important limitation of online/mobile maps that presents risks to user safety and the environment. In order to address this limitation, a large-scale means of mapping SURs must be developed. In this paper, we introduce and motivate the problem of mapping space usage rules and take the first steps towards identifying solutions. We show how computer vision can be employed to identify SUR indicators in the environment (e.g. "No Smoking" signs) with reasonable accuracy and describe techniques that can assign each rule to the appropriate geographic feature.

Map applications for smartwatches present new challenges in cartography, a domain in which large display sizes have significant advantages. In this paper, we introduce StripeMaps, a system that adapts the mobile web design technique of linearization for displaying maps on the small screens of smartwatches. Just as web designers simplify multiple column desktop websites into a single column for easier navigation on mobile devices, StripeMaps transforms any two-dimensional route map into a one-dimensional "stripe". Through a user study, we show that this simplification allows StripeMaps to outperform both traditional mobile map interfaces and turn-by-turn directions for pedestrian navigation using smartwatches. In addition to introducing StripeMaps, this paper also has a secondary contribution. It contains the first empirical comparison of different approaches for pedestrian smartwatch navigation and illuminates their pros and cons.

In the age of mobile communications and social media, users are connected to interact with other people, and often obliged to be socially active as technology drives to connect us. In this paper, we harness the technology for the opposite use: helping people to avoid company instead of encouraging interaction. We have developed the concept of an asocial hiking application (app), in which users can generate routes that avoid meeting other people. We developed the concept based on user feedback data derived from an online survey (n=157) and two focus groups, and created a tool that generates solitary hiking routes based on OpenStreetMap data and additional information from the web. In addition, to make the application react to dynamic changes in the environment, we developed a mobile application prototype that scans Wi-Fi signals to detect other hikers nearby and warn of their approach. The prototype was tested and evaluated with 8 hikers in-the-wild. In addition to the concept design and the functional prototype, we present findings on people's, especially hikers, need for solitude, and introduce user feedback from each stage of the prototype design process as well as design recommendations for an asocial navigation application.

Despite the large and growing prominence of online and mobile maps, they have not been broadly and systematically examined with a lens informed by traditional cartography. Using an approach rooted in cartographic theory and a unique dataset of 382 publicly-displayed local maps, we identify the collective wisdom of hundreds of cartographers with respect to a number of cartographic design decisions. We compare our findings to the approaches taken in popular online and mobile map platforms and develop suggestions for incorporating the collective wisdom of cartographers into these systems. Our suggestions include the adoption of location-aware cartography, in which cartographic approaches are intelligently varied based on the type of location being viewed. We provide mockup designs of online and mobile maps that implement our suggestions and discuss means by which the surprising gap between online and mobile maps and traditional cartography may be bridged.

We present the concept of highly deformable mobile devices that can be transformed into various special-purpose controls in order to bring physical controls to mobile devices. Physical controls have the advantage of exploiting people's innate abilities for manipulating physical objects in the real world. We designed and implemented a prototype, called Paddle, to demonstrate our concept. Additionally, we explore the interaction techniques enabled by this concept and conduct an in-depth study to evaluate our transformable physical controls. Our findings show that these physical controls provide several benefits over traditional touch interaction techniques commonly used on mobile devices.

During remote video-mediated assistance, instructors often guide workers through problems and instruct them to perform unfamiliar or complex operations. However, the workers' performance might deteriorate due to stress. We argue that informing biofeedback to the instructor, can improve communication and lead to lower stress. This paper presents a thorough investigation on mental workload and stress perceived by twenty participants, paired up in an instructor-worker scenario, performing remote video-mediated tasks. The interface conditions differ in task, facial and biofeedback communication. Two self-report measures are used to assess mental workload and stress. Results show that pairs reported lower mental workload and stress when instructors are using the biofeedback as compared to using interfaces with facial view. Significant correlations were found on task performance with reducing stress (i.e. increased task engagement and decreased worry) for instructors and declining mental workload (i.e. increased performance) for workers. Our findings provide insights to advance video-mediated interfaces for remote collaborative work.

Thanks to rapid advances in technologies like GPS and Wi-Fi positioning, smartphone users are able to determine their location almost everywhere they go. This is not true, however, of people who are traveling in underground public transportation networks, one of the few types of high-traffic areas where smartphones do not have access to accurate position information. In this paper, we introduce the problem of underground transport positioning on smartphones and present SubwayPS, an accelerometer-based positioning technique that allows smartphones to determine their location substantially better than baseline approaches, even deep beneath city streets. We highlight several immediate applications of positioning in subway networks in domains ranging from mobile advertising to mobile maps and present MetroNavigator, a proof-of-concept smartphone and smartwatch app that notifies users of upcoming points-of-interest and alerts them when it is time to get ready to exit the train.

Non-verbal and unconscious behavior plays an important role for efficient human-to-human communication but are often undervalued when training people to become better communicators. This is particularly true for public speakers who need not only behave according to a social etiquette but do so while generating enthusiasm and interest for dozens if not hundreds of other persons. In this paper we propose the concept of social augmentation using wearable computing with the goal of giving users the ability to continuously monitor their performance as a communicator. To this end we explore interaction modalities and feedback mechanisms which would lend themselves to this task.

We describe FoodBoard, an instrumented chopping board that uses optical fibers and embedded camera imaging to identify unpackaged ingredients during food preparation on its surface. By embedding the sensing directly, and robustly, in the surface of a chopping board we also demonstrate how surface contact optical sensing can be used to realize the portability and privacy required of technology used in a setting such as a domestic kitchen. FoodBoard was subjected to a close to real-world evaluation in which 12 users prepared actual meals. FoodBoard compared favourably with existing unpackaged food recognition systems, classifying a larger number of distinct food ingredients (12 incl. meat, fruit, vegetables) with an average accuracy of 82.8%.

Intelligent User Interfaces can benefit from having knowledge on the user's emotion. However, current implementations to detect affective states, are often constraining the user's freedom of movement by instrumenting her with sensors. This prevents affective computing from being deployed in naturalistic and ubiquitous computing contexts. In this paper, we present a novel system called mASqUE, which uses a set of association rules to infer someone's affective state from their body postures. This is done without any user instrumentation and using off-the-shelf and non-expensive commodity hardware: a depth camera tracks the body posture of the users and their postures are also used as an indicator of their openness. By combining the posture information with physiological sensors measurements we were able to mine a set of association rules relating postures to affective states. We demonstrate the possibility of inferring affective states from body postures in ubiquitous computing environments and our study also provides insights how this opens up new possibilities for IUI to access the affective states of users from body postures in a nonintrusive way.

Exploratory search, in which a user investigates complex concepts, is cumbersome with today's search engines. We present a new exploratory search approach that generates interactive visualizations of query concepts using thematic cartography (e.g. choropleth maps, heat maps). We show how the approach can be applied broadly across both geographic and non-geographic contexts through explicit spatialization, a novel method that leverages any figure or diagram -- from a periodic table, to a parliamentary seating chart, to a world map -- as a spatial search environment. We enable this capability by introducing explanatory semantic relatedness measures. These measures extend frequently-used semantic relatedness measures to not only estimate the degree of relatedness between two concepts, but also generate human-readable explanations for their estimates by mining Wikipedia's text, hyperlinks, and category structure. We implement our approach in a system called Atlasify, evaluate its key components, and present several use cases.

Interactive surfaces have great potential for co-located collaboration because of their ability to track multiple inputs simultaneously. However, the multi-user experience on these devices could be enriched significantly if touch points could be associated with a particular user. Existing approaches to user identification are intrusive, require users to stay in a fixed position, or suffer from poor accuracy. We present a non-intrusive, high-accuracy technique for mapping touches to their corresponding user in a collaborative environment. By mounting a high-resolution camera above the interactive surface, we are able to identify touches reliably without any extra instrumentation, and users are able to move around the surface at will. Our technique, which leverages the back of users' hands as identifiers, supports walk-up-and-use situations in which multiple people interact on a shared surface.

The increasing number of media facades in urban spaces offers great potential for new forms of interaction especially for collaborative multi-user scenarios. In this paper, we present a way to directly interact with them through live video on mobile devices. We extend the Touch Projector interface to accommodate multiple users by showing individual content on the mobile display that would otherwise clutter the facade's canvas or distract other users. To demonstrate our concept, we built two collaborative multi-user applications: (1) painting on the facade and (2) solving a 15-puzzle. We gathered informal feedback during the ARS Electronica Festival in Linz, Austria and found that our interaction technique is (1) considered easy-to-learn, but (2) may leave users unaware of the actions of others.

Cars offer an increasing number of infotainment systems as well as comfort functions that can be controlled by the driver. In our research, we investigate new interaction techniques that aim to make it easier to interact with these systems while driving. We suggest utilizing the steering wheel as an additional interaction surface. In this paper, we present two user studies conducted with a working prototype of a multi-touch steering wheel. In the first, we developed a user-defined steering wheel gesture set, and in the second, we applied the identified gestures and compared their application to conventional user interaction with infotainment systems in terms of driver distraction. The main outcome was that driver's visual demand is reduced significantly by using gestural interaction on the multi-touch steering wheel.

There are a number of mobile shopping aids and recommender systems available, but none can be easily used for a weekly shop at a local supermarket. We present a minimal, mobile and fully functional lambent display that clips onto any shopping trolley handle, intended to nudge people when choosing what to buy. It provides salient information about the food miles for various scanned food items represented by varying lengths of lit LEDs on the handle and a changing emoticon comparing the average miles of all the products in the trolley against a social norm. When evaluated in situ, the lambent handle display nudged people to choose products with fewer food miles than the items they selected using their ordinary shopping strategies. People also felt guilty when the average mileage of the contents of their entire shopping trolley was above the social norm. The findings are discussed in terms of how to provide different kinds of product information that people care about, using simple lambent displays.

The electronic market has rapidly grown in the last few years. However, despite this success, consumers still enjoy visiting a store with real products. Therefore various common technologies have been installed in supermarkets to support the customer's shopping process and experience. In this paper, we introduce the IRL SmartCart - an instrumented shopping cart that acts as a user interface to support the shopping process. We show how RFID technology enables recognizing products that are put in the cart's basket. We are also able to determine the cart's position in an instrumented shopping environment. User input and visual output are possible by means of a touch screen, which is fitted in the IRL SmartCart's handle to support different tasks involved in the shopping process. We present and discuss different location- and context-based services that run on the cart interface system, e.g. a personalized shopping list sorted corresponding to the products in the user's vicinity or a navigation service to different products that the customer is searching for.

While applications for mobile devices have become extremely important in the last few years, little public information exists on mobile application usage behavior. We describe a large-scale deployment-based research study that logged detailed application usage information from over 4,100 users of Android-powered mobile devices. We present two types of results from analyzing this data: basic descriptive statistics and contextual descriptive statistics. In the case of the former, we find that the average session with an application lasts less than a minute, even though users spend almost an hour a day using their phones. Our contextual findings include those related to time of day and location. For instance, we show that news applications are most popular in the morning and games are at night, but communication applications dominate through most of the day. We also find that despite the variety of apps available, communication applications are almost always the first used upon a device's waking from sleep. In addition, we discuss the notion of a virtual application sensor, which we used to collect the data.

Shopping is one of the most frequently occuring tasks in our daily lives, and creation and management of shopping lists is an important aspect of this task. Given the recent adoption of mobile devices, the process of writing lists is not only limited to the use of pen and paper, as a good number of digital tools and applications are available. The goal of this paper is to study and understand the transition between paper-based and digital shopping lists. We analyze how people interact with paper-based shopping lists and derive design implications for our own hybrid shopping support application, which combines paper-based lists with a mobile application. We contribute the study and the design and implementation of a hybrid (pen-and-paper-based UI and mobile GUI) application for the creation of shopping lists.

Projector phones, handheld game consoles and many other mobile devices increasingly include more than one display, and therefore present a new breed of mobile Multi-Display Environments (MDEs) to users. Existing studies illustrate the effects of visual separation between displays in MDEs and suggest interaction techniques that mitigate these effects. Currently, mobile devices with heterogeneous displays such as projector phones are often designed without reference to visual separation issues; therefore it is critical to establish whether concerns and opportunities raised in the existing MDE literature apply to the emerging category of Mobile MDEs (MMDEs). This paper investigates the effects of visual separation in the context of MMDEs and contrasts these with fixed MDE results, and explores design factors for Mobile MDEs. Our study uses a novel eye-tracking methodology for measuring switches in visual context between displays and identifies that MMDEs offer increased design flexibility over traditional MDEs in terms of visual separation. We discuss these results and identify several design implications.

We present iPiccer, a system that allows mobile camera phones users to interact with meta-tagged image material available from web repositories, such as flickr in two novel ways. Users of the system are able to infer photo tags from their location and orientation, but are also able to infer their location and orientation from their spatial photo tags. An implementation of iPiccerTaker is outlined, and the potential of this new form of interaction with web repository data is discussed.

We conducted a user study to investigate the effect of visual context in handheld augmented reality interfaces. A dynamic peephole interface (without visual context beyond the device display) was compared to a magic lens interface (with video see-through augmentation of external visual context). The task was to explore objects on a map and look for a specific attribute shown on the display. We tested different sizes of visual context as well as different numbers of items per area, i.e. different item densities. We found that visual context is most effective for sparse item distributions and the performance benefit decreases with increasing density. User performance in the magic lens case approaches the performance of the dynamic peephole case the more densely spaced the items are. In all conditions, subjective feedback indicates that participants generally prefer visual context over the lack thereof. The insights gained from this study are relevant for designers of mobile AR and dynamic peephole interfaces by suggesting when external visual context is most beneficial.

In many mid- to large-sized cities public maps are ubiquitous. One can also find a great number of maps in parks or near hiking trails. Public maps help to facilitate orientation and provide special information to not only tourists but also to locals who just want to look up an unfamiliar place while on the go. These maps offer many advantages compared to mobile maps from services like Google Maps Mobile or Nokia Maps. They often show local landmarks and sights that are not shown on standard digital maps. Often these 'You are here' (YAH) maps are adapted to a special use case, e.g. a zoo map or a hiking map of a certain area. Being designed for a fashioned purpose these maps are often aesthetically well designed and their usage is therefore more pleasant. In this paper we present a novel technique and application called PhotoMap that uses images of 'You are here' maps taken with a GPS-enhanced mobile camera phone as background maps for on-the-fly navigation tasks. We discuss different implementations of the main challenge, namely helping the user to properly georeference the taken image with sufficient accuracy to support pedestrian navigation tasks. We present a study that discusses the suitability of various public maps for this task and we evaluate if these georeferenced photos can be used for navigation on GPS-enabled devices.

Classic paper-based maps provide high-resolution, large-scale information and are ubiquitous in larger cities and even outdoors. In this paper we present a combination of their advantages with a mobile camera projector unit to create a new mobile and intuitive buddy finder interface. Current friend or buddy finder systems on mobile phones such as Google Latitude suffer from the small screen estate and display size of mobile devices. To overcome this problem we use a lightweight mobile camera projector unit to augment the paper map with a projected overlay of the buddies' positions. By using digital and geo-referenced representations of public maps no extra preperation for the tracking is needed. The idea is presented by enhancing Google Latitude, which allows users to browse the positions of their friends, to project the positions directly on the paper map without the cumbersome panning and zooming of a digital map on a small display.

This paper presents the general idea of image geo-mashups, which combines concepts from web mashups and augmented reality by adding geo-referenced data to a perspective image. The paper shows how to design and implement an augmented reality weather cam, that combines data from a steerable weather cam with additional sensor information retrieved from the web.

Virtual globes have progressed from little-known technology to broadly popular software in a mere few years. We investigated this phenomenon through a survey and discovered that, while virtual globes are en vogue, their use is restricted to a small set of tasks so simple that they do not involve any spatial thinking. Spatial thinking requires that users ask "what is where" and "why"; the most common virtual globe tasks only include the "what". Based on the results of this survey, we have developed a multi-touch virtual globe derived from an adapted virtual globe paradigm designed to widen the potential uses of the technology by helping its users to inquire about both the "what is where" and "why" of spatial distribution. We do not seek to provide users with full GIS (geographic information system) functionality, but rather we aim to facilitate the asking and answering of simple "why" questions about general topics that appeal to a wide virtual globe user base.

A user study was conducted to compare the performance of three methods for map navigation with mobile devices. These methods are joystick navigation, the dynamic peephole method without visual context, and the magic lens paradigm using external visual context. The joystick method is the familiar scrolling and panning of a virtual map keeping the device itself static. In the dynamic peephole method the device is moved and the map is fixed with respect to an external frame of reference, but no visual information is present outside the device's display. The magic lens method augments an external content with graphical overlays, hence providing visual context outside the device display. Here too motion of the device serves to steer navigation. We compare these methods in a study measuring user performance, motion patterns, and subjective preference via questionnaires. The study demonstrates the advantage of dynamic peephole and magic lens interaction over joystick interaction in terms of search time and degree of exploration of the search space.