In this work, we explore attacker behavior during shoulder surfing. As such behavior is often opportunistic and difficult to observe in real world settings, we leverage the capabilities of virtual reality (VR). We recruited 24 participants and observed their behavior in two virtual waiting scenarios: at a bus stop and in an open office space. In both scenarios, participants shoulder surfed private screens displaying different types of content. From the results we derive an understanding of factors influencing shoulder surfing behavior, reveal common attack patterns, and sketch a behavioral shoulder surfing model. Our work suggests directions for future research on shoulder surfing and can serve as a basis for creating novel approaches to mitigate shoulder surfing.

The availability of consumer-grade virtual reality (VR) devices allows user studies to be conducted remotely, that is in users’ homes. In this way, diverse populations can be reached and studies using virtual reality can be conducted in settings characterized by high ecologic validity. In this study (N=21) we investigate challenges participants face as they are required to set up and calibrate a virtual reality system in their home without assistance from experimenters. This allowed us to identify key reasons why participants struggle with this task. Our findings suggest that providing illustrative instructions and additional assistance on request can notably increase the success rate of setting up a VR environment for participating in a remote study. Interestingly, we also find that it is harder to recruit participants who do not have prior VR experience to participate in remote VR studies. We derive suggestions on how to support this task based on our findings.

Tablets are attractive for design work anywhere, but 3D manipulations are notoriously difficult. We explore how engaging the stylus and multi-touch in concert can render such tasks easier. We introduce Bi-3D, an interaction concept where touch gestures are combined with 2D pen commands for 3D manipulation. For example, for a fast and intuitive 3D drag & drop technique: the pen drags the object on-screen, and parallel pinch-to-zoom moves it in the third dimension. In this paper, we describe the Bi-3D design space, crossing two-handed input and the degrees-of-freedom (DOF) of 3D manipulation and navigation tasks. We demonstrate sketching and manipulation tools in a prototype 3D design application, where users can fluidly combine 3D operations through alternating and parallel use of the modalities. We evaluate the core technique, bi-manual 3DOF input, against widget and mid-air baselines in an object movement task. We find that Bi-3D is a fast and practical way for multi-dimensional manipulation of graphical objects, promising to facilitate 3D design on stylus and tablet devices.

We investigate opportunities and challenges of running virtual reality (VR) studies remotely. Today, many consumers own head-mounted displays (HMDs), allowing them to participate in scientific studies from their homes using their own equipment. Researchers can benefit from this approach by being able to recruit study populations normally out of their reach, and to conduct research at times when it is difficult to get people into the lab (cf. the COVID pandemic). In an initial online survey ( N = 227), we assessed HMD owners’ demographics, their VR setups and their attitudes toward remote participation. We then identified different approaches to running remote studies and conducted two case studies for an in-depth understanding. We synthesize our findings into a framework for remote VR studies, discuss strengths and weaknesses of the different approaches, and derive best practices. Our work is valuable for Human-Computer Interaction (HCI) researchers conducting VR studies outside labs.

Field studies on public displays can be difficult, expensive, and time-consuming. We investigate the feasibility of using virtual reality (VR) as a test-bed to evaluate deployments of public displays. Specifically, we investigate whether results from virtual field studies, conducted in a virtual public space, would match the results from a corresponding real-world setting. We report on two empirical user studies where we compared audience behavior around a virtual public display in the virtual world to audience behavior around a real public display. We found that virtual field studies can be a powerful research tool, as in both studies we observed largely similar behavior between the settings. We discuss the opportunities, challenges, and limitations of using virtual reality to conduct field studies, and provide lessons learned from our work that can help researchers decide whether to employ VR in their research and what factors to account for if doing so.

The button is an element of a user interface to trigger an action, traditionally using click or touch. We introduce GazeButton, a novel concept extending the default button mode with advanced gaze-based interactions. During normal interaction, users can utilise this button as a universal hub for gaze-based UI shortcuts. The advantages are: 1) easy to integrate in existing UIs, 2) complementary, as users choose either gaze or manual interaction, 3) straightforward, as all features are located in one button, and 4) one button to interact with the whole screen. We explore GazeButtons for a custom-made text reading, writing, and editing tool on a multitouch tablet device. For example, this allows the text cursor position to be set as users look at the position and tap on the GazeButton, avoiding costly physical movement. Or, users can simply gaze over a part of the text that should be selected, while holding the GazeButton. We present a design space, specific application examples, and point to future button designs that become highly expressive by unifying the user's visual and manual input.