EDBT 2026 Demo / reviewers in the wild / expert
Michael Saker
dblp:175/4911
· DBLP profile ↗
14ranked-venue papers
0as first author
11since 2021 · last 2026
0000-0002-7414-2840ORCID · corroborated
Domains — the database's venue-derived domains; a paper can count in several
Human-computer interaction and ubiquitous computing · 14 · 11 since 2021
| Year | Publication | Venue | Position |
|---|---|---|---|
| 2026 | Understanding the Dynamics of Trust in Location-Based Games as Hybrid Spaces: The Players' PerspectiveabstractLocation-based games (LBGs) merge digital play with physical environments, creating hybrid spaces that require players to navigate complex trust dynamics. Despite their global popularity, LBGs introduce unique challenges around fairness, safety, and privacy, spanning interactions among players, game systems, local communities, and non-players in shared public spaces. To examine how trust is perceived, built, and sustained in these environments, we conducted in-depth interviews with 26 players of four major LBGs: Pokémon GO, Monster Hunter Now, Ingress, and Pikmin Bloom. Using reflexive thematic analysis, we identified dynamics of trust across four trustor–trustee relationships: player–system, player–player, player–community, and player–non-player in five key aspects: fair play, location privacy, online vetting, hybrid interaction, and public play. Drawing on our findings, we propose a trust model for analyzing and designing trust in LBGs as hybrid spaces, and we outline design implications aimed at strengthening trust building and sustaining trustworthy interactions across the LBG ecology. Jiangnan Xu, Sanzida Mojib Luna, Michael Saker, Alan Chamberlain, Nicolas J. LaLone, Samuli Laato, Garreth W. Tigwell, Konstantinos Papangelis |
CHI | 3 |
| 2026 | Understanding Spatiotemporal-Aware Multimodal Conversational Search in the Outdoor Urban SpaceabstractEmerging multimodal conversational search (MCS) tools (e.g., Gemini Live) allow users to search for spatiotemporal information through natural language dialogues as they move through urban space. Despite the growing popularity of these tools, there is limited understanding of how people engage with this technology. To address this gap, we developed UrbanSearch, an MCS technology probe designed to capture the user’s current geolocation, time, and visual surroundings. A contextual inquiry (N=23) revealed that MCS tools provide two core values: requiring low effort in forming queries while offering highly relevant responses, and functioning as a central information gateway. As a promising technology, MCS supports environmental learning, in-situ decision making, and personalized navigation. Participants also revealed unmet needs for spatial reasoning and transparent integration of multi-source information, along with concerns related to peripheral awareness, social context, and personal space. Drawing from the findings, we discuss design implications for future MCS tools in urban spaces. Jiangnan Xu, Suyeon Seo, Joni Salminen, Michael Saker, Joon Gi Shin, Alan Chamberlain, Konstantinos Papangelis, Daehyun Kim 0005 |
CHI | 4 |
| 2025 | Exploring Deaf And Hard of Hearing Peoples' Perspectives On Tasks In Augmented Reality: Interacting With 3D Objects And Instructional ComprehensionabstractTasks in augmented reality (AR), such as 3D interaction and instructional comprehension, are often designed for users with uniform sensory abilities. Such an approach, however, can overlook the more nuanced needs of Deaf and Hard of Hearing (DHH) users who might have reduced auditory perception. To better understand these challenges, our study utilized the single-player AR game Angry Birds AR as a probe to explore how 11 DHH participants and 15 hearing participants experienced AR interactions. Our findings highlight that DHH users prefer interaction based on context, effective haptic cues, audio cue substitutes, and clear instructional design. We, therefore, propose the following design recommendations to enhance the accessibility of AR for DHH users. This includes customizable UI options, modular feedback systems, and virtual avatars for sign language instructions. Sanzida Mojib Luna, Jiangnan Xu, Garreth W. Tigwell, Nicolas J. LaLone, Michael Saker, Alan Chamberlain, David I. Schwartz, Konstantinos Papangelis |
CHI | 5 |
| 2025 | Understanding the Interplay between the Digital and the Physical in Shared AR Gaming: Probing through Urban LegendsabstractShared Augmented Reality (Shared AR) is an emerging technology that enables multiple users to interact synchronously within a collocated AR environment. Yet, there is limited research on the group interactions and dynamics in Shared AR, particularly in the context of gaming. To address this gap, we investigate Shared AR group interactions using a phone-based Shared AR mobile game called Urban Legends . Through in situ observations, focus groups, and one-on-one interviews with 22 participants, we examine how users collaborate and communicate within the game. Our findings reveal that while verbal communication predominates, non-verbal cues are often overlooked by collocated participants, and users initially struggle to recognize the expansive virtual space and the need for physical movement. Over time, users adapt to the hybrid environment, demonstrating increasing spatial awareness and more dynamic collaboration. Based on these insights, we present a suite of design recommendations for enhancing spatial awareness, supporting multi-modal communication, and fostering engaging group dynamics in future Shared AR applications. Jiangnan Xu, Sanzida Mojib Luna, Garreth W. Tigwell, Nicolas J. LaLone, Michael Saker, Samuli Laato, John Dunham, Alan Chamberlain, Konstantinos Papangelis |
ACM Trans. Comput. Hum. Interact. | 5 |
| 2024 | Communication, Collaboration, and Coordination in a Co-located Shared Augmented Reality Game: Perspectives From Deaf and Hard of Hearing PeopleabstractCo-located collaborative shared augmented reality (CS-AR) environments have gained considerable research attention, mainly focusing on design, implementation, accuracy, and usability. Yet, a gap persists in our understanding regarding the accessibility and inclusivity of such environments for diverse user groups, such as deaf and Hard of Hearing (DHH) people. To investigate this domain, we used Urban Legends, a multiplayer game in a co-located CS-AR setting. We conducted a user study followed by one-on-one interviews with 17 DHH participants. Our findings revealed the usage of multimodal communication (verbal and non-verbal) before and during the game, impacting the amount of collaboration among participants and how their coordination with AR components, their surroundings, and other participants improved throughout the rounds. We utilize our data to propose design enhancements, including onscreen visuals and speech-to-text transcription, centered on participant perspectives and our analysis. Sanzida Mojib Luna, Jiangnan Xu, Konstantinos Papangelis, Garreth W. Tigwell, Nicolas J. LaLone, Michael Saker, Alan Chamberlain, Samuli Laato, John Dunham |
CHI | 6 |
| 2023 | Building Positively Affective Location-Based Advertising: A Study of Pokémon GO PlayersabstractWith the expanding popularity of Location-Based Games and the rise of advertising therein, there exists a need to comprehend the impact of Location-Based Game Advertising (LGA). This paper seeks to identify what makes positively affective LGA, leveraging Pokémon GO as a probe. Researchers conducted twenty-seven (n=27) semi-structured interviews with Pokémon GO players to reveal lived experiences regarding LGA. Our findings highlight the following direct implications for LGA: (1) LGA act as a digital billboard, conveying qualitative alongside locative information, and (2) well-received LGA enhances the player’s agency. We additionally identify findings that have auxiliary implications to LGA: (3) positive memorability occurs when points of interest match physical reality, and (4) ludic engagement is a mediating factor in the memorability of locations. This research demonstrates that LGA in Location-Based Games is surprisingly well-received. However, developers must provide extra consideration to the player’s agency for such techniques to be effective. John Dunham, Konstantinos Papangelis, Cati Boulanger, Nicolas J. LaLone, Evangelia Nika, Michael Saker, David I. Schwartz |
CHI | 6 |
| 2023 | Tasks of a Different Color: How Crowdsourcing Practices Differ per Complex Task Type and Why This MattersabstractCrowdsourcing in China is a thriving industry. Among its most interesting structures, we find crowdfarms, in which crowdworkers self-organize as small organizations to tackle macrotasks. Little, however, is known as to which practices these crowdfarms use to tackle the macrotasks, and this goes hand in hand with the current practice of the HCI research community to treat all forms of complex crowdsourcing work as practically the same. However, macrotasks differ substantially regarding structure and decomposability. Treating them under one umbrella term - macrotasking - can lead to an imprecise understanding of the workforce involved. We address this gap by examining the work practices of 31 Chinese crowdfarms on the four main macrotask types, namely: modular, interlaced, wicked, and container macrotasks. Our results confirm essential differences in how these nascent crowd organizations address different macrotasks and shed light on what platforms can do to improve the uptake of such work. Konstantinos Papangelis, Ioanna Lykourentzou, Michael Saker, Alan Chamberlain, Vassilis-Javed Khan, Hai-Ning Liang, Yong Yue 0001 |
CHI | 4 |
| 2023 | Understanding Social Interactions in Location-based Games as Hybrid Spaces: Coordination and Collaboration in Raiding in Pokémon GOabstractThe overlaying of physical spaces with digital information produces hybrid spaces, redefining people’s experience of social interactions. Location-based games (LBGs) with social components are a good case. Yet, the impact LBGs have on sociability remains under-researched. In April 2020, the new in-person/remote raiding format in the LBG Pokémon GO provided a lens to explore people’s social interactions in hybrid spaces. We interviewed 41 Pokémon GO players to understand how players coordinate and collaborate for in-person/remote raids and other social patterns. Our findings demonstrate that new social dynamics occurred: participants’ social interactions highly rely on external social media groups bridging cyberspace and the physical world. In such external social media groups, spontaneously formed leadership roles and mentor-mentee relationships demonstrate autonomy among players in the hybrid space. However, we observed that the interoperability issue challenges people’s experience. Overall, this work sheds light on the social interactions in LBGs as hybrid spaces. Jiangnan Xu, Konstantinos Papangelis, John Dunham, Cati Boulanger, Jin Ha Lee 0001, Nicolas J. LaLone, Michael Saker |
CHI | 7 |
| 2023 | Introduction to Smart Cities in Transition: Challenges of Participation in Urban EnvironmentsabstractThe continued development of smart cities is a recurring feature of urban living and does not appear to be slowing down. Today, our lives are both mediated and monitored by a range of digital techn... Konstantinos Papangelis, Michael Saker, Dale Leorke, Jin Ha Lee 0001, Catherine Jones |
Int. J. Hum. Comput. Interact. | 2 |
| 2023 | The Impacts of Covid-19 on Players of Pokémon GOabstractSince its creation, the Location-Based Game (LBG), Pokémon GO , has been embraced by a community of fans across the world. Due to its recency, the impact of COVID-19 on the community of Pokémon GO players is underexplored. We address how COVID-19 has impacted the players of Pokémon GO by building upon existing work focusing on player gratifications and impacts in Pokémon GO . Through semi-structured interviews, we provide a snapshot of the state of LBG play during unprecedented times. These player interviews demonstrate (1) the importance of in-person socialization to LBG, (2) additional ways players use the game as a coping mechanism, and (3) how intentionality mediates player perceptions of people-place relationships. Furthermore, we explore how Niantic influenced these behaviors through changes to how players interact with points of interest and engage with elder game mechanics such as raiding. John Dunham, Konstantinos Papangelis, Samuli Laato, Nicolas J. LaLone, Jin Ha Lee 0001, Michael Saker |
ACM Trans. Comput. Hum. Interact. | 6 |
| 2021 | An Examination of the Work Practices of CrowdfarmsabstractCrowdsourcing is a new value creation business model. Annual revenue of the Chinese market alone is hundreds of millions of dollars, yet few studies have focused on the practices of the Chinese crowdsourcing workforce, and those that do mainly focus on solo crowdworkers. We have extended our study of solo crowdworker practices to include crowdfarms, a relatively new entry to the gig economy: small companies that carry out crowdwork as a key part of their business. We report here on interviews of people who work in 53 crowdfarms. We describe how crowdfarms procure jobs, carry out macrotasks and microtasks, manage their reputation, and employ different management practices to motivate crowdworkers and customers. Konstantinos Papangelis, Michael Saker, Ioanna Lykourentzou, Vassilis-Javed Khan, Alan Chamberlain, Jonathan Grudin |
CHI | 3 |
| 2020 | Crowdsourcing in China: Exploring the Work Experiences of Solo Crowdworkers and Crowdfarm WorkersabstractRecent research highlights the potential of crowdsourcing in China. Yet very few studies explore the workplace context and experiences of Chinese crowdworkers. Those that do, focus mainly on the work experiences of solo crowdworkers but do not deal with issues pertaining to the substantial amount of people working in 'crowdfarms'. This article addresses this gap as one of its primary concerns. Drawing on a study that involves 48 participants, our research explores, compares and contrasts the work experiences of solo crowdworkers to those of crowdfarm workers. Our findings illustrate that the work experiences and context of the solo workers and crowdfarm workers are substantially different, with regards to their motivations, the ways they engage with crowdsourcing, the tasks they work on, and the crowdsourcing platforms they utilize. Overall, our study contributes to furthering the understandings on the work experiences of crowdworkers in China. Konstantinos Papangelis, Michael Saker, Ioanna Lykourentzou, Alan Chamberlain, Vassilis-Javed Khan |
CHI | 3 |
| 2020 | Smart Cities at Play: Technology and Emerging forms of playfulnessabstractSmart cities are commonly described as ‘places where information technology is combined with infrastructure, architecture, everyday objects, and even our bodies to address social, economic, and env... Konstantinos Papangelis, Michael Saker, Catherine Jones |
Behav. Inf. Technol. | 2 |
| 2020 | Performing the Digital Self: Understanding Location-Based Social Networking, Territory, Space, and Identity in the CityabstractExpressions of territoriality have been positioned as one of the main reasons users alter their behaviors and perceptions of spatiality and sociality while engaging with location-based social networks (LBSN). Despite the potential for this interplay to further our understanding of LBSN usage in the context of identity, very little work has actually been done toward this. Addressing this gap in the literature is one of the chief aims of the article. Drawing on an original 6-week study with 42 participants utilizing a bespoke LBSN entitled “GeoMoments,” our research explores the following: (1) the way that territoriality is linked to self-identity; and (2) how this interplay affects the interactions between users as well as the environments they inhabit. Our findings suggest that participants affirmed their self-identity by selectively posting and claiming ownership of their neighborhood through the LBSN. Here, the locative decisions are made related to risk, hierarchies, and the users’ relationship to the area. This practice then led participants to discover and interact with the digital information overlaying their physical environments in a playful manner. These interactions demonstrate the perceived power structures that are facilitated by identity claims over a virtual area. In the main, our results reaffirm that territoriality is a central concept in understanding LBSN use, while also drawing attention to the temporality involved in user-to-user and user-to-place interactions pertaining to physical place mediated by LBSN. Konstantinos Papangelis, Alan Chamberlain, Ioanna Lykourentzou, Vassilis-Javed Khan, Michael Saker, Hai-Ning Liang, Irwyn Sadien |
ACM Trans. Comput. Hum. Interact. | 5 |