User interface personalization enhances digital efficiency, usability, and accessibility. However, in user-driven setups, limited support for identifying and evaluating worthwhile opportunities often leads to underuse. We explore a reflexive personalization approach where individuals engage with their digital interaction data to identify meaningful personalization opportunities and benefits. We interviewed 12 participants, using experimental vignettes as design probes to support reflection on different forms of using interaction data to empower decision-making in personalization and the preferred level of system support. We found that people can independently identify personalization opportunities but prefer system support through visual personalization suggestions. Interaction data can shape how users perceive and approach personalization by reinforcing the perceived value of change and data collection, helping them weigh benefits against effort, and increasing the transparency of system suggestions. We discuss opportunities for designing personalization software that raises end-users’ agency over interfaces through reflective engagement with their interaction data.

Self-tracking tools are often built around the assumption that tracking the “right” health variables will lead to actionable insights and greater control over one’s health. Yet, it remains unclear how these assumptions hold up in contexts marked by uncertainty, unpredictability, and frequent fluctuations in health needs. We explore this question in the management of enigmatic diseases—conditions such as fibromyalgia, Crohn’s disease, and endometriosis that are poorly understood and highly individualized. Through interviews with 23 participants living with disparate enigmatic conditions, we examine goals, motivations, and how tracking practices evolve across different disease states. Our findings show that tracking was strongly shaped by shifting needs, with goals emerging, evolving, or being abandoned in response to health fluctuations. Tracking was often double-edged: at times empowering, fostering a sense of control, but also frustrating, leading to self-blame and negative views of everyday activities being tracked.

As populations age and technology becomes more pervasive, understanding the alignment between older adults’ values and technology design is paramount. More research is needed to understand how older adults’ living contexts shape their values and the use of technology. To address this, through a multi-context study, we explored how values differ for older adults and how their context of living might influence the adoption and use of technology. We conducted 22 semi-structured interviews with older adults in various residential contexts. We show that older adults tend to prioritize the same core values across living contexts, yet how they express values in each context differs. Technology can amplify or inhibit key values. We describe implications for context-responsive technology and design for continuity, to allow older adults to continually uphold important values through technology use.

Human-Robot Interaction (HRI) research in real-world settings may lead to unanticipated, emotionally charged moments. While impacts of these moments on participants are reported in the literature, researchers’ emotions, which can affect participants’ experiences, are often left unreported. Learning from these moments is essential for advancing HRI quality and real-world deployment success. We introduce "Emotional Entanglements" as a lens in HRI to define a researcher's capacity to anticipate, absorb, respond to, and recover from emotionally impactful events. Collecting testimonials using collaborative autoethnography from eleven researchers, we surface recurring emotional entanglements experienced in HRI studies, including tears with mixed meaning, participant attachment and loss upon robot withdrawal, and consequential participant decisions attributed to the robot, as well as how researchers navigated them amidst protocol constraints. This paper provides an actionable guide to "Emotional Sustainability in HRI", raising awareness of these often unreported situations and offering strategies for mitigation.

Introductory coding environments have been used in early education to promote computational thinking, supporting the development of cognitive, critical, and social skills. Many environments focus on individual use, which has limited benefits compared to collaborative learning. In this paper, we present the results of a 10-session study at a local primary school engaging eleven children with visual impairments and three inclusive education teachers in collaborative programming activities. Based on participants' behavior, reactions, and feedback, we contribute an improved understanding of collaborative design in educational settings, focusing on the impact of Goals, Workspace, Interdependence, and Shared Awareness. Our main findings outline how collaboration dynamics can be shaped by asymmetric tasks, workspace proximity, and group awareness. We further discuss factors that led to a lack of investment in the shared goal and instances of unbalanced collaboration, reflecting on challenges and opportunities for designing collaborative inclusive coding kits.

Providing care to individuals with chronic diseases benefits from a multidisciplinary approach and longitudinal symptom, event, and disease monitoring, in and out of clinical facilities. Technological advancements, including the ubiquitous presence of sensors and devices, present opportunities to collect large amounts of data and extract evidence-based insights about the patient and disease. Nevertheless, practical examples of clinical utility of those technologies remain sparse, and in specific focus areas (e.g, insights from a single device). This paper explores the challenges and opportunities of multidisciplinary clinical dashboards to support clinicians caring for people with chronic diseases. We report on a focus group and co-design workshops with a multidisciplinary team of clinicians and HCI researchers. We offer insights into how technological outcomes and visualizations can enhance clinical practice and the intricacies of information-sharing dynamics. We discuss the potential of dashboards to trigger actions in clinical settings and emphasize the benefits of customizable dashboards.

In multiplayer gaming, skill disparity can lead to frustrating and excluding experiences. Balancing approaches exist to level the playing field (e.g., providing aim assistance to low-performing players), but it is unclear how different design choices affect individual player experience. We first introduce a design space for balancing mechanics encompassing six categories: Determination, Timing, Targeting, Effect, Feedback, and Information. We then present a mixed-methods study, focused on the effect of two subcategories: Targeting Direction and Effect Dependency on skill. In this study, eight pairs of participants played a game prototype and experienced seven balancing mechanics. We collected data from questionnaires and group interviews, revealing implications for future designs, including the importance of 1) merited victory that does not ignore individual achievements, 2) sense of agency when determining the balancing before and during gameplay, and 3) balancing as an intrinsic part of the game that does not disrupt the core gameplay.

Abstract Exposure therapy (ET) gradually introduces people to the objects, animals, or situations they fear to help them overcome the angst with that source of anxiety. VR(ET) enables exposure to various triggers in the safety of the clinical or home environments. While prior work has explored how specific VR environments support therapy in contexts such as social anxiety or arachnophobia, therapy’s individualised nature is often overlooked. We used an iterative participatory design approach to develop an authoring platform for therapists, enabling them to tailor VR environments during exposure by changing and parameterising elements and reapplying past scenes. We used this platform as a design probe in a study with ten therapists to elicit discussions about the design of VRET experiences and therapists’ authoring needs. Findings highlight the value of controlling the stimuli presented to patients and deviating from stereotypical scenarios, and the importance of further investigating the therapist’s virtual representation.

User interface (UI) personalization can improve usability and user experience. However, current systems offer limited opportunities for customization, and third-party solutions often require significant effort and technical skills beyond the reach of most users, impeding the future adoption of interface personalization. In our research, we explore the concept of UI customization for the self and others. We performed a two-week study where nine participants used a custom-designed tool that allows websites' UI customization for oneself and to create and reply to customization assistance requests from others. Results suggest that people enjoy customizing for others more than for themselves. They see requests as challenges to solve and are motivated by the positive feeling of helping others. To customize for themselves, people need help with the creative process. We discuss challenges and opportunities for future research seeking to democratize access to personalized UIs, particularly through community-based approaches.

For families, where abilities, motivations, and availability vary widely, opportunities for intergenerational play are limited. Designing games that cater to these differences remains an open challenge. In this paper, we first identify barriers related with time and expertise. Next, we propose asymmetric game design and asynchronous play to reconcile children's and adults' requirements; and interdependent gameplay mechanics to foster real-world interactions. Following this approach, we designed a testbed game and conducted a mixed-methods remote study with six pairs of adult-child family members. Our results showcase how asymmetric, asynchronous experiences can be leveraged to create novel gaming experiences that meet the requirements of family play. We discuss how interdependent progress can be designed to promote real-world interactions, creating pervasive conversational topics that permeate the family routine.

Playful robotics engages children in learning through play experiences while simultaneously developing critical thinking, and social, cognitive, and motor skills through play. Such playful experiences are particularly valuable in inclusive education to promote social and inclusive behaviors. We present TACTOPI, an inclusive and playful multisensory environment that leverages tangible interaction and a robot as the main character. We investigate how TACTOPI supports play in 10 dyads of children with mixed visual abilities. Results show that multisensory elements supported children to experience activities as joyful. Storytelling and guided-play added a layer of meaningfulness to the activities, and the robot engaged children in minds-on thinking. TACTOPI afforded children to engage in collaborative social play and facilitated supportive and inclusive behaviours. We contribute with a playful multisensory environment, an analysis of the effect of its components on social, cognitive, and inclusive play, and design considerations for inclusive multisensory environments that prioritize play.

We rely on large-scale web accessibility evaluations to obtain snapshots of Internet Health and understand trends and behaviours impacting overall web accessibility. Such evaluations are financially and time exhaustive, making the possibility of more real-time measurements of Internet Health infeasible. In this paper, we investigate the impacts of optimising the page selection processes of large-scale web accessibility evaluations. We set out to conduct an automated accessibility evaluation of 1500 websites using the ‘Home+’ sampling method (for each website, we evaluated the home page and all pages linked belonging to the same domain) as our baseline; then compared the agreement rates of web accessibility evaluations on further sub-sampled datasets. Accessibility data was successfully captured on 987 websites. Our findings demonstrate that a strong accessibility evaluation agreement between the baseline and the sub-sample datasets could be reached with a sub-sample of just 20% of the pages, significantly reducing the effort and resources required to conduct large-scale web accessibility evaluations.

Collaborative coding environments foster learning, social skills, computational thinking training, and supportive relationships. In the context of inclusive education, these environments have the potential to promote inclusive learning activities for children with mixed-visual abilities. However, there is limited research focusing on remote collaborative environments, despite the opportunity to design new modes of access and control of content to promote more equitable learning experiences. We investigated the tradeoffs between remote and co-located collaboration through a tangible coding kit. We asked ten pairs of mixed-visual ability children to collaborate in an interdependent and asymmetric coding game. We contribute insights on six dimensions - effectiveness, computational thinking, accessibility, communication, cooperation, and engagement - and reflect on differences, challenges, and advantages between collaborative settings related to communication, workspace awareness, and computational thinking training. Lastly, we discuss design opportunities of tangibles, audio, roles, and tasks to create inclusive learning activities in remote and co-located settings.

User-generated content plays a key role in social networking, allowing a more active participation, socialisation, and collaboration among users. In particular, media content has been gaining a lot of ground, allowing users to express themselves through different types of formats such as images, GIFs and videos. The majority of this growing type of online visual content remains inaccessible to a part of the population, in particular for those who have a visual disability, despite available tools to mitigate this source of exclusion. We sought to understand how people are perceiving this type of online content in their networks and how support tools are being used. To do so, we conducted a user study, with 258 social network users through an online questionnaire, followed by interviews with 20 of them – 7 blind users and 13 sighted users. Results show how the different approaches being employed by major platforms may not be sufficient to address this issue properly. Our findings reveal that users are not always aware of the possibility and the benefits of adopting accessible practices. From the general perspectives of end-users experiencing accessible practices, concerning barriers encountered, and motivational factors, we also discuss further approaches to create more user engagement and awareness.

Typing on mobile devices is a common and complex task. The act of typing itself thereby encodes rich information, such as the typing method, the context it is performed in, and individual traits of the person typing. Researchers are increasingly using a selection or combination of experience sampling and passive sensing methods in real-world settings to examine typing behaviours. However, there is limited understanding of the effects these methods have on measures of input speed, typing behaviours, compliance, perceived trust and privacy. In this paper, we investigate the tradeoffs of everyday data collection methods. We contribute empirical results from a four-week field study (N=26). Here, participants contributed by transcribing, composing, passively having sentences analyzed and reflecting on their contributions. We present a tradeoff analysis of these data collection methods, discuss their impact on text-entry applications, and contribute a flexible research platform for in the wild text-entry studies.

Virtual Reality (VR) has become a mainstream opportunity to develop immersive environments where people are exposed to relevant stimuli in a systematic but safe way. Besides the controlled exposure to stimuli, VR systems enable a more efficient and unbiased gathering of information with practical applications in diagnosis, intervention, and health monitoring processes. Nonetheless, scientific literature has demonstrated that interacting with VR technology and its peripherals can be challenging, especially in populations less familiar with technology (e.g., older adults) or with clinical conditions that are not adequately accommodated by the technology, such as cognitive (e.g., dementia) or physical impairments (e.g., blindness). This workshop will focus on systems, technological approaches, and theoretical frameworks to develop user/patient-centred VR tools for diagnosis, intervention, and monitoring of health and wellbeing outcomes. Moreover, we welcome work focused on accessibility issues, aiming to promote equal access and opportunity to use VR tools by people with diverse abilities.

Accessible introductory programming environments are scarce, and their study within ecological settings (e.g., at home) is almost non-existent. We present ACCembly, an accessible block-based environment that enables children with visual impairments to perform spatial programming activities. ACCembly allows children to assemble tangible blocks to program a multimodal robot. We evaluated this approach with seven families that used the system autonomously at home. Results showed that both the children and family members learned from what was an inclusive and engaging experience. Children leveraged fundamental computational thinking concepts to solve spatial programming challenges; parents took different roles as mediators, some actively teaching and scaffolding, others learning together with their child. We contribute with an environment that enables children with visual impairments to engage in spatial programming activities, an analysis of parent-child interactions, and reflections on inclusive programming environments within a shared family experience.

Virtual environments for therapy are scarce and lack personalization. The creation of these environments is done by specialists, is time-consuming, and expensive. We present a smartphone tool that allows non-specialists to create navigable virtual environments by taking and linking sequences of panoramic photo spheres, analogly to Google Street View. Editing the environments is then possible in a web platform, myView, where text, images, videos, sounds, and pick-up objects can be added. myView allows users to navigate their environments as well as sharing those environments with others. In a preliminary study with two psychologists, where myView was used as an elicitation probe, the approach was found to be useful for creating meaningful activities for reminiscence and cognitive training. The platform showed to be promising in the democratization of the crafting of virtual environments.

Smartphones are shipped with built-in screen readers and other accessibility features that enable blind people to autonomously learn and interact with the device. However, the process is not seamless, and many face difficulties in the adoption and path to becoming more experienced users. In the past, games like Minesweeper served to introduce and train people in the use of the mouse, from its left and right click to precision pointing required to play the game. Smartphone gestures (and particularly screen reader gestures) pose similar challenges to the ones first faced by mouse users. In this work, we explore the use of games to inconspicuously train gestures. We designed and developed a set of accessible games, enabling users to practice smartphone gestures. We evaluated the games with 8 blind users and conducted remote interviews. Our results show how purposeful accessible games could be important in the process of training and discovering smartphone gestures, as they offer a playful method of learning. This, in turn, increases autonomy and inclusion, as this process becomes easier and more engaging.

Introduction of computational thinking training in early childhood potentiates cognitive development and better prepares children to live and prosper in a future heavily computational society. Programming environments are now widely adopted in classrooms to teach programming concepts. However, these tools are often reliant on visual interaction, making them inaccessible to children with visual impairments. Also, programming environments in general are usually designed to promote individual experiences, wasting the potential benefits of group collaborative activities. We propose the design of a programming environment that leverages asymmetric roles to foster collaborative computational thinking activities for children with visual impairments, in particular mixed-visual-ability classes. The multimodal system comprises the use of tangible blocks and auditory feedback, while children have to collaborate to program a robot. We conducted a remote online study, collecting valuable feedback on the limitations and opportunities for future work, aiming to potentiate education and social inclusion.

The landscape of digital games is segregated by player ability. For example, sighted players have a multitude of highly visual games at their disposal, while blind players may choose from a variety of audio games. Attempts at improving cross-ability access to any of those are often limited in the experience they provide, or disregard multiplayer experiences. We explore ability-based asymmetric roles as a design approach to create engaging and challenging mixed-ability play. Our team designed and developed two collaborative testbed games exploring asymmetric interdependent roles. In a remote study with 13 mixed-visual-ability pairs we assessed how roles affected perceptions of engagement, competence, and autonomy, using a mixed-methods approach. The games provided an engaging and challenging experience, in which differences in visual ability were not limiting. Our results underline how experiences unequal by design can give rise to an equitable joint experience.

Previous attempts to make block-based programming accessible to visually impaired children have mostly focused on audio-based challenges, leaving aside spatial constructs, commonly used in learning settings. We sought to understand the qualities and flaws of current programming environments in terms of accessibility in educational settings. We report on a focus group with IT and special needs educators, where they discussed a variety of programming environments for children, identifying their merits, barriers and opportunities. We then conducted a workshop with 7 visually impaired children where they experimented with a bespoke tangible robot-programming environment. Video recordings of such activity were analyzed with educators to discuss children's experiences and emergent behaviours. We contribute with a set of qualities that programming environments should have to be inclusive to children with different visual abilities, insights for the design of situated classroom activities, and evidence that inclusive tangible robot-based programming is worth pursuing.

The usage of playful activities is common in introductory programming settings. There is normally a virtual character or a physical robot that has to collect items or reach a goal within a map. Visually, these activities tend to be exciting enough to maintain children engaged: there is constant feedback about the actions being performed, and the virtual environments tend to be stimulating and aesthetically pleasant. Conversely, in adaptations for visually impaired children, these environments tend to become poorer, damaging the story at the cost of the programming actions and its dull mechanics (e.g., place a arrow block to move the character forward). In this paper, we present TACTOPI, a playful environment designed from the ground up to be rich in both its story (a nautical game) and its mechanics (e.g., a physical robot-boat controlled with a 3D printed wheel), tailored to promote computational thinking at different levels (4 to 8 years old). This poster intends to provoke discussion and motivate accessibility researchers that are interested in computational thinking to make playfulness a priority.

Games bring people together in immersive and challenging interactions. In this paper, we share multiplayer gaming experiences of people with visual impairments collected from interviews with 10 adults and 10 minors, and 140 responses to an online survey. We include the perspectives of 17 sighted people who play with someone who has a visual impairment, collected in a second online survey. Our focus is on group play, particularly on the problems and opportunities that arise from mixed-visual-ability scenarios. These show that people with visual impairments are playing diverse games, but face limitations in playing with others who have different visual abilities. What stands out is the lack of intersection in gaming opportunities, and consequently, in habits and interests of people with different visual abilities. We highlight barriers associated with these experiences beyond inaccessibility issues and discuss implications and opportunities for the design of mixed-ability gaming.

Blind people face significant challenges when using smartphones. The focus on improving nonvisual mobile accessibility has been at the level of touchscreen access. Our research investigates the challenges faced by blind people in their everyday usage of mobile phones. In this article, we present a set of studies performed with the target population, novices and experts, using a variety of methods, targeted at identifying and verifying challenges; and coping mechanisms. Through a multiple methods approach we identify and validate challenges locally with a diverse set of user expertise and devices, and at scale through the analyses of the largest Android and iOS dedicate forums for blind people. We contribute with a prioritized corpus of smartphone challenges for blind people, and a discussion on a set of directions for future research, which tackle the open and often overlooked challenges.

We present iCETA, an inclusive interactive system for math learning, that enables children to autonomously engage and solve additive composition tasks. It was designed through a set of participatory sessions with visually impaired children and their educators, and supports math learning through the combination of tangible interaction with haptic and auditory feedback. Tangible blocks representing numbers 1 to 5 were used to add or subtract and correctly solve the task embedded in a computerized game. Our approach aims to provide better scaffolding for understanding the abstract concept of a number by working with different representations of that number, as the size of the block, Braille, color and audio feedback.

Word completion interfaces are ubiquitously available in mobile virtual keyboards; however, there is no prior research on how to design these interfaces for screen reader users. In addressing this, we propose a design space for nonvisual representation of word completions. The design space covers seven categories aiming to identify challenges and opportunities for interaction design in an unexplored research topic. It is intended to guide the design of novel interaction techniques, serving as a framework for researchers and practitioners working on nonvisual word completion. To demonstrate its potential, we engaged blind users in an exploration of the design space, to create their own bespoke word completion solutions. Through this study we found that users create alternative interfaces that extended current screen readers' capabilities. Resulting interfaces are less conservative than mainstream solutions on notification frequency and cardinality. Customization decisions were based on perceived benefits/costs and varied depending on multiple factors such as users' perceived prediction accuracy, potential keystroke gains, and situational restrictions.

Unauthorized physical access to personal devices by people known to the owner of the device is a common concern, and a common occurrence. But how do people experience incidents of unauthorized access? Using an online survey, we collected 102 accounts of unauthorized access. Participants wrote stories about past situations in which either they accessed the smartphone of someone they know, or someone they know accessed theirs. We describe the context leading up to these incidents, the course of events, and the consequences. We then identify two orthogonal themes in how participants conceptualized these incidents. First, participants understood trust as performative vulnerability: trust was necessary to sustain relationships, but building trust required displaying vulnerability to breaches. Second, participants were self-serving in their sensemaking: they blamed the circumstances, or the other person's shortcomings, but rarely themselves. We discuss the implications of our findings for security design and practice.

Our goal is to disseminate an exploratory investigation that examined how physical presence and collaboration can be important factors in the development of assistive robots that can go beyond information-giving technologies. In particular, this video exhibits the setting and procedures of a user study that explored different types of collaborative interactions between robots and blind people.

Blind people rely on sighted peers and different assistive technologies to accomplish everyday tasks. In this paper, we explore how assistive robots can go beyond information-giving assistive technologies (e.g., screen readers) by physically collaborating with blind people. We first conducted a set of focus groups to assess how blind people perceive and envision robots. Results showed that, albeit having stereotypical concerns, participants conceive the integration of assistive robots in a broad range of everyday life scenarios and are welcoming of this type of technology. In a second study, we asked blind participants to collaborate with two versions of a robot in a Tangram assembly task: one robot would only provide static verbal instructions whereas the other would physically collaborate with participants and adjust the feedback to their performance. Results showed that active collaboration had a major influence on the successful performance of the task. Participants also reported higher perceived warmth, competence and usefulness when interacting with the physically assistive robot. Overall, we provide preliminary results on the usefulness of assistive robots and the possible role these can hold in fostering a higher degree of autonomy for blind people.

Braille input enables fast nonvisual entry speeds on mobile touchscreen devices. Yet, the lack of tactile cues commonly results in typing errors, which are hard to correct. We propose Hybrid-Brailler, an input solution that combines physical and gestural interaction to provide fast and accurate Braille input. We use the back of the device for physical chorded input while freeing the touchscreen for gestural interaction. Gestures are used in editing operations, such as caret movement, text selection, and clipboard control, enhancing the overall text entry experience. We conducted two user studies to assess both input and editing performance. Results show that Hybrid-Brailler supports fast entry rates as its virtual counterpart, while significantly increasing input accuracy. Regarding editing performance, when compared with the mainstream technique, Hybrid-Brailler shows performance benefits of 21% in speed and increased editing accuracy. We finish with lessons learned for designing future nonvisual input and editing techniques.

Blind people face many barriers using smartphones. Still, previous research has been mostly restricted to non-visual gestural interaction, paying little attention to the deeper daily challenges of blind users. To bridge this gap, we conducted a series of workshops with 42 blind participants, uncovering application challenges across all levels of expertise, most of which could only be surpassed through a support network. We propose Hint Me!, a human-powered service that allows blind users to get in-app assistance by posing questions or browsing previously answered questions on a shared knowledge-base. We evaluated the perceived usefulness and acceptance of this approach with six blind people. Participants valued the ability to learn independently and anticipated a series of usages: labeling, layout and feature descriptions, bug workarounds, and learning to accomplish tasks. Creating or browsing questions depends on aspects like privacy, knowledge of respondents and response time, revealing the benefits of a hybrid approach.

The physical keypads that used to dominate our mobile devices provided additional support for non-visual interaction - the keys could be recognized tactually, the interfaces were simpler and consistent. When combined with a screen reader, these devices could be easily operated by blind people. The advent of smartphones, with their rich, feature-filled applications and interfaces, have brought forward additional challenges for blind users. Apps and features are no longer developed by a single entity leading to an overwhelming variety of interfaces. We present an approach that superimposes a virtual overlay to all other interfaces ensuring interface consistency by re-structuring how content is accessed in every screen. To explore the approach, we split the screen, dedicating half to a configurable set of static options mimicking always available physical buttons regardless of context; while the other enables the standard content navigation gestures with the ability to re-order content and apply filters. In a qualitative study with nine visually impaired participants, the virtual overlays were reported as simpler to use, while still providing full-fledged usage of the system and the third party applications, and were seen as effective and useful, particularly for novice users.

Facebook accounts are secured against unauthorized access through passwords and device-level security. Those defenses, however, may not be sufficient to prevent social insider attacks, where attackers know their victims, and gain access to a victim's account by interacting directly with their device. To characterize these attacks, we ran two MTurk studies. In the first (n = 1,308), using the list experiment method, we estimated that 24% of participants had perpetrated social insider attacks and that 21% had been victims (and knew about it). In the second study (n = 45), participants wrote stories detailing personal experiences with such attacks. Using thematic analysis, we typified attacks around five motivations (fun, curiosity, jealousy, animosity, and utility), and explored dimensions associated with each type. Our combined findings indicate that social insider attacks are common, often have serious emotional consequences, and have no simple mitigation.

Touch-enabled devices have a growing variety of screen sizes; however, there is little knowledge on the effect of key size on non-visual text-entry performance. We conducted a user study with 12 blind participants to investigate how non-visual input performance varies with four QWERTY keyboard sizes (ranging from 15mm to 2.5mm). This paper presents an analysis of typing performance and touch behaviors discussing its implications for future research. Our findings show that there is an upper limit to the benefits of larger target sizes between 10mm and 15mm. Input speed decreases from 4.5 to 2.4 words per minute (WPM) for targets sizes below 10mm. The smallest size was deemed unusable by participants even though performance was in par with previous work.

Most work investigating mobile HCI is carried out within controlled laboratory settings; these spaces are not representative of the real-world environments for which the technology will predominantly be used. The result of which can produce a skewed or inaccurate understanding of interaction behaviors and users-- abilities. While mobile in-the-wild studies provide more realistic representations of technology usage, there are additional challenges to conducting data collection outside of the lab. In this paper we discuss these challenges and present TinyBlackBox, a standalone data collection framework to support mobile in-the-wild studies with today--s smartphone and tablet devices.

Non-visual text-entry for people with visual impairments has focused mostly on the comparison of input techniques reporting on performance measures, such as accuracy and speed. While researchers have been able to establish that non-visual input is slow and error prone, there is little understanding on how to improve it. To develop a richer characterization of typing performance, we conducted a longitudinal study with five novice blind users. For eight weeks, we collected in-situ usage data and conducted weekly laboratory assessment sessions. This paper presents a thorough analysis of typing performance that goes beyond traditional aggregated measures of text-entry and reports on character-level errors and touch measures. Our findings show that users improve over time, even though it is at a slow rate (0.3 WPM per week). Substitutions are the most common type of error and have a significant impact on entry rates. In addition to text input data, we analyzed touch behaviors, looking at touch contact points, exploration movements, and lift positions. We provide insights on why and how performance improvements and errors occur. Finally, we derive some implications that should inform the design of future virtual keyboards for non-visual input.

The advent of system-wide accessibility services on mainstream touch-based smartphones has been a major point of inclusion for blind and visually impaired people. Ever since, researchers aimed to improve the accessibility of specific tasks, such text-entry and gestural interaction. However, little work aimed to understand and improve the overall accessibility of these devices in real world settings. In this paper, we present an eight-week long study with five novice blind participants where we seek to understand major concerns, expectations, challenges, barriers, and experiences with smartphones. The study included pre-adoption and weekly interviews, weekly controlled task assessments, and in-the wild system-wide usage. Our results show that mastering these devices is an arduous and long task, confirming the users' initial concerns. We report on accessibility barriers experienced throughout the study, which could not be encountered in task-based laboratorial settings. Finally, we discuss how smartphones are being integrated in everyday activities and highlight the need for better adoption support tools.

Accessibility research studies often gather subjective responses to technology using Likert-type items, where participants respond to a prompt statement by selecting a position on a labeled response scale. We analyzed recent ASSETS papers, and found that participants in non-anonymous accessibility research studies gave more positive average ratings than those in typical usability studies, especially when responding to questions about a proposed innovation. We further explored potential positive response bias in an experimental study of two telephone information systems, one more usable than the other. We found that participants with visual impairment were less sensitive to usability problems than participants in a typical student sample, and that their subjective ratings didn't correlate as strongly with objective measures of performance. A deeper understanding of the mechanism behind this effect would help researchers to design better accessibility studies, and to interpret subjective ratings with more accuracy.

Tablet devices can display full-size QWERTY keyboards similar to the physical ones. Yet, the lack of tactile feedback and the inability to rest the fingers on the home keys result in a highly demanding and slow exploration task for blind users. We present SpatialTouch, an input system that leverages previous experience with physical QWERTY keyboards, by supporting two-handed interaction through multitouch exploration and spatial, simultaneous audio feedback. We conducted a user study, with 30 novice touchscreen participants entering text under one of two conditions: (1) SpatialTouch or (2) mainstream accessibility method Explore by Touch. We show that SpatialTouch enables blind users to leverage previous experience as they do a better use of home keys and perform more efficient exploration paths. Results suggest that although SpatialTouch did not result in faster input rates overall, it was indeed able to leverage previous QWERTY experience in contrast to Explore by Touch.

Braille has paved its way into mobile touchscreen devices, providing faster text input for blind people. This advantage comes at the cost of accuracy, as chord typing over a flat surface has proven to be highly error prone. A misplaced finger on the screen translates into a different or unrecognized character. However, the chord itself gathers information that can be leveraged to improve input performance. We present B#, a novel correction system for multitouch Braille input that uses chords as the atomic unit of information rather than characters. Experimental results on data collected from 11 blind people revealed that B# is effective in correcting errors at character-level, thus providing opportunities for instant corrections of unrecognized chords; and at word-level, where it outperforms a popular spellchecker by providing correct suggestions for 72% of incorrect words (against 38%). We finish with implications for designing chord-based correction system and avenues for future work.

Despite the overwhelming emergence of accessible digital technologies, Braille still plays a role in providing blind people with access to content. Nevertheless, many fail to see the benefits of nurturing Braille, particularly given the time and effort required to achieve proficiency. Our research focuses on maximizing access and motivation to learn and use Braille. We present initial insights from 5 interviews with blind people, comprising of Braille instructors and students, where we characterize the learning process and usage of Braille. Based on our findings, we have identified a set of opportunities around Braille education. Moreover, we devised scenarios, and built hardware and software solutions to motivate discovery and retention of Braille literacy.

Blind people typically resort to audio feedback to access information on electronic devices. However, this modality is not always an appropriate form of output. Novel approaches that allow for private and inconspicuous interaction are paramount. In this paper, we present a vibrotactile reading device that leverages the users' Braille knowledge to read textual information. UbiBraille consists of six vibrotactile actuators that are used to code a Braille cell and communicate single characters. The device is able to simultaneously actuate the users' index, middle, and ring fingers of both hands, providing fast and mnemonic output. We conducted two user studies on UbiBraille to assess both character and word reading performance. Character recognition rates ranged from 54% to 100% and were highly character- and user-dependent. Indeed, participants with greater expertise in Braille reading/writing were able to take advantage of this knowledge and achieve higher accuracy rates. Regarding word reading performance, we investigated four different vibrotactile timing conditions. Participants were able to read entire words and obtained recognition rates up to 93% with the most proficient ones being able achieve a rate of 1 character per second.

The emergence of touch-based mobile devices brought fresh and exciting possibilities. These came at the cost of a considerable number of novel challenges. They are particularly apparent with the blind population, as these devices lack tactile cues and are extremely visually demanding. Existing solutions resort to assistive screen reading software to compensate the lack of sight, still not all the information reaches the blind user. Good spatial ability is still required to have notion of the device and its interface, as well as the need to memorize buttons' position on screen. These abilities, as many other individual attributes as age, age of blindness onset or tactile sensibility are often forgotten, as the blind population is presented with the same methods ignoring capabilities and needs. Herein, we present a study with 13 blind people consisting of a touch screen text-entry task with four different methods. Results show that different capability levels have significant impact on performance and that this impact is related with the different methods' demands. These variances acknowledge the need of accounting for individual characteristics and giving space for difference, towards inclusive design.

Touch screen mobile devices bear the promise of endless leisure, communication, and productivity opportunities to motor-impaired people. Indeed, users with residual capacities in their upper extremities could benefit immensely from a device with no demands regarding strength. However, the precision required to effectively select a target without physical cues creates problems to people with limited motor abilities. Our goal is to thoroughly study mobile touch screen interfaces, their characteristics and parameterizations, thus providing the tools for informed interface design for motor-impaired users. We present an evaluation performed with 15 tetraplegic people that allowed us to understand the factors limiting user performance within a comprehensive set of interaction techniques (Tapping, Crossing, Exiting and Directional Gesturing) and parameterizations (Position, Size and Direction). Our results show that for each technique, accuracy and precision vary across different areas of the screen and directions, in a way that is directly dependent on target size. Overall, Tapping was both the preferred technique and among the most effective. This proves that it is possible to design inclusive unified interfaces for motor-impaired and able-bodied users once the correct parameterization or adaptability is assured.

Mobile devices are designed mostly to fit users with no particular disability. Tactile affordances are neglected at the expense of more attractive stylish interfaces and assistive solutions are stereotypical, also facing disabilities with a narrow perspective. A blind user is presented with screen reading software to overcome the inability to receive feedback from the device. However, these solutions go only half-way. In the absence of sight other capabilities stand up. Above all, the sense of touch plays an essential role while interacting with physical keypads. To empower these users, a deeper understanding of their capabilities and how they relate with technology is mandatory. We propose a user-product compatibility approach, taking in account that blind users have different tactile attributes. We expect to correlate the user's tactile sensitivity and keypad demands, enabling informed keypad design and selection.

Every human is different. This diversity has not been given enough attention in mobile UI design. Disabled groups, with specific individual differences, face difficulties with traditional or stereotypical interfaces. My goal is to identify the individual features that influence mobile interaction, considering the blind, and match them with mobile interaction modalities in a comprehensive and extensible design space.

The proliferation of personal devices and their constant awareness of our interactions have generated an enormous amount of data that can be useful to help the user obtaining relevant information when needed. Our approach uses the personal information on users' devices, together with public online sources, to provide relevant information from the user point of view. The information from the users' devices, due to its personal and credible character, works as a filter to the retrieved from other less trustable and structured sources. A preliminary evaluation, suggested that we can provide the user with inter-connected relevant information from heterogeneous sources. However, we found some limitations that led us to our current research challenges.

Mobile touch-screen interfaces and tetraplegic people have a controversial connection. While users with residual capacities in their upper extremities could benefit immensely from a device which does not require strength to operate, the precision needed to effectively select a target bars these people access to countless communication, leisure and productivity opportunities. Insightful projects attempted to bridge this gap via either special hardware or particular interface tweaks. Still, we need further insight into the challenges and the frontiers separating failure from success for such applications to take hold. This paper discusses an evaluation conducted with 15 tetraplegic people to learn the limits to their performance within a comprehensive set of interaction methods. We then present the results concerning a particular interaction technique: Tapping. Results show that performance varies across different areas of the screen whose distribution changes with target size.

NavTap is a navigational method that enables blind users to input text in a mobile device by reducing the associated cognitive load.

We present a framework to manage multimodal applications and interfaces in a reusable and extensible manner. We achieve this by focusing the architecture both on applications' needs and devices' capabilities. One particular domain we want to approach is collaborative environments where several modalities and applications make it necessary to provide for an extensible system combining diverse components across heterogeneous platforms on-the-fly. This paper describes the proposed framework and its main contributions in the context of an architectural application scenario. We demonstrate how to connect different non-conventional applications and input modalities around an immersive environment (tiled display wall).