Understanding How Mobile Interactions Shape Grasp and Contact Patterns Beyond the TouchscreenThe 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.2026CSCarolin Stellmacher et al.University of BremenOne-Handed Operation & Mobile GesturesTouch Target Selection & PointingCHI
Experiencing the World through Imperfect Lenses: An Autoethnography of Living in Mixed RealityMixed 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.2025YSYu Sun et al.Mixed Reality WorkspacesImmersion & Presence ResearchContext-Aware ComputingDIS
UrbAI: Exploring the Possibilities of Generative AI Image Processing to Promote Citizen ParticipationGiving 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.2025APAdrian Preussner et al.University of St. GallenGenerative AI (Text, Image, Music, Video)Community Engagement & Civic TechnologyCHI
Describing Explored Places through OpenStreetMap DataMobile 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.2025ESEve Schade et al.University of St. GallenGeospatial & Map VisualizationPublic Transit & Trip PlanningCHI
DIY Digital Interventions: Behaviour Change with Trigger-Action ProgrammingWhether 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.2024ASAva Elizabeth Scott et al.Creative Collaboration & Feedback SystemsKnowledge Worker Tools & WorkflowsMobileHCI
MoodShaper: A Virtual Reality Experience to Support Managing Negative EmotionsNegative 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 either 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.2024NWNadine Wagener et al.Immersion & Presence ResearchVR Medical Training & RehabilitationMental Health Apps & Online Support CommunitiesDIS
Exploring Mobile Devices as Haptic Interfaces for Mixed RealityDedicated 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.2024CSCarolin Stellmacher et al.University of BremenShape-Changing Interfaces & Soft Robotic MaterialsMixed Reality WorkspacesCHI
Playing with Perspectives and Unveiling the Autoethnographic Kaleidoscope in HCI – A Literature Review of AutoethnographiesAutoethnography 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.2024AKAnnika Kaltenhauser et al.University of St. GallenUser Research Methods (Interviews, Surveys, Observation)Field StudiesCHI
Experiencing Dynamic Weight Changes in Virtual Reality Through Pseudo-Haptics and Vibrotactile FeedbackVirtual 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.2024CSCarolin Stellmacher et al.University of BremenVibrotactile Feedback & Skin StimulationForce Feedback & Pseudo-Haptic WeightCHI
Children with ADHD and their Care Ecosystem: Designing Beyond SymptomsDesigning 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.2023ESEvropi Stefanidi et al.University of BremenCognitive Impairment & Neurodiversity (Autism, ADHD, Dyslexia)Special Education TechnologyUser Research Methods (Interviews, Surveys, Observation)CHI
MapUncover: Fostering Spatial Exploration through Gamification in Mobile Map AppsGetting 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.2023ESEve Schade et al.University of St. GallenGeospatial & Map VisualizationGamification DesignContext-Aware ComputingCHI
Mood Worlds: A Virtual Environment for Autonomous Emotional ExpressionImmersive 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.2022NWNadine Wagener et al.University of BremenSocial & Collaborative VRImmersion & Presence ResearchInteractive Narrative & Immersive StorytellingCHI