Silent speech input converts non-acoustic features like tongue and lip movements into text. It has been demonstrated as a promising input method on mobile devices and has been explored for a variety of audiences and contexts where the acoustic signal is unavailable (e.g., people with speech disorders) or unreliable (e.g., noisy environment). Though the method shows promise, very little is known about peoples’ perceptions regarding using it. In this work, first, we conduct two user studies to explore users’ attitudes towards the method with a particular focus on social acceptance and error tolerance. Results show that people perceive silent speech as more socially acceptable than speech input and are willing to tolerate more errors with it to uphold privacy and security. We then conduct a third study to identify a suitable method for providing real-time feedback on silent speech input. Results show users find an abstract feedback method effective and significantly more private and secure than a commonly used video feedback method.

Social contexts play an important role in understanding acceptance and use of technology. However, current approaches used in HCI to describe contextual influence do not capture it appropriately. On the one hand, the often used Technology Acceptance Model and related frameworks are too rigid to account for the nuanced variations of social situations. On the other hand, Goffman’s dramaturgical model of social interactions emphasizes interpersonal relations but mostly overlooks the material (e.g., technology) that is central to HCI. As an alternative, we suggest an approach based on Social Practice Theory. We conceptualize social context as interactions between co-located social practices and acceptability as a matter of their (in)compatibilities. Finally, we outline how this approach provides designers with a better understanding of different types of social acceptability problems and helps finding appropriate solutions.

Augmented Reality (AR) glasses equip users with the tools to modify the visual appearance of their surrounding environment. This might severely impact interpersonal communication, as the conversational partners will no longer share the same visual perception of reality. Grounded in color-in-context theory, we present a potential AR application scenario in which users can modify the color of the environment to achieve subconscious benefits. In a consecutive online survey (N=64), we measured the user’s comfort, acceptance of altering and being altered, and how it is impacted by being able to perceive or not perceive the alteration. We identified significant differences depending on (1) who or what is the target of the alteration, (2) which body part is altered, and (3) which relationship the conversational partners share. In light of our quantitative and qualitative findings, we discuss ethical and practical implications for future devices and applications that employ visual alterations.

Blind people have limited access to information about their surroundings, which is important for ensuring one's safety, managing social interactions, and identifying approaching pedestrians. With advances in computer vision, wearable cameras can provide equitable access to such information. However, the always-on nature of these assistive technologies poses privacy concerns for parties that may get recorded. We explore this tension from both perspectives, those of sighted passersby and blind users, taking into account camera visibility, in-person versus remote experience, and extracted visual information. We conduct two studies: an online survey with MTurkers (N=206) and an in-person experience study between pairs of blind (N=10) and sighted (N=40) participants, where blind participants wear a working prototype for pedestrian detection and pass by sighted participants. Our results suggest that both of the perspectives of users and bystanders and the several factors mentioned above need to be carefully considered to mitigate potential social tensions.

On-face wearables are currently limited to piercings, tattoos, or interactive makeup that aesthetically enhances the user, and have been minimally used for scent-delivery methods. However, on-face scent interfaces could provide an advantage for personal scent delivery in comparison with other modalities or body locations since they are closer to the nose. In this paper, we present the mechanical and industrial design details of a series of form factors for on-face olfactory wearables that are lightweight and can be adhered to the skin or attached to glasses or piercings. We assessed the usability of three prototypes by testing with 12 participants in a within-subject study design while they were interacting in pairs at a close personal distance. We compare two of these designs with an "off-face" olfactory necklace and evaluate their social acceptance, comfort as well as perceived odor intensity for both the wearer and observer.

Wearable devices have received tremendous interest in fitness and personal assistance sectors. Yet most are still worn as auxiliary hardware; falling short in ubiquity and convenience. We examine the potential of a novel deformable wearable device that embeds interactive technologies into garment buttons, and seek to enhance the form factor of buttons to incorporate deformation and motion as inputs. We surveyed garment buttons in everyday clothing to inform an exploratory study, where we investigated social acceptance and elicited interaction gestures using mockups. Our results indicate people mostly prefer smaller sizes, and regard sleeves as the most comfortable area to operate and look at when seen by others. Based on our findings, we discuss potential context of use, possible applications, and future work.

Understanding social perception is important for designing mobile devices that are socially acceptable. Previous work not only investigated the social acceptability of mobile devices and interaction techniques but also provided tools to measure social acceptance. However, we lack a robust model that explains the underlying factors that make devices socially acceptable. In this paper, we consider mobile devices as social objects and investigate if the stereotype content model (SCM) can be applied to those devices. Through a study that assesses combinations of mobile devices and group stereotypes, we show that mobile devices have a systematic effect on the stereotypes' warmth and competence. Supported by a second study, which combined mobile devices without a specific stereotypical user, our result suggests that mobile devices are perceived stereotypically by themselves. Our combined results highlight mobile devices as social objects and the importance of considering stereotypes when assessing social acceptance of mobile devices.

Virtual reality (VR) headsets allow wearers to escape their physical surroundings, immersing themselves in a virtual world. Although escape may not be realistic or acceptable in many everyday situations, air travel is one context where early adoption of VR could be very attractive. While travelling, passengers are seated in restricted spaces for long durations, reliant on limited seat-back displays or mobile devices. This paper explores the social acceptability and usability of VR for in-flight entertainment. In an initial survey, we captured respondents' attitudes towards the social acceptability of VR headsets during air travel. Based on the survey results, we developed a VR in-flight entertainment prototype and evaluated this in a focus group study. Our results discuss methods for improving the acceptability of VR in-flight, including using mixed reality to help users transition between virtual and physical environments and supporting interruption from other co-located people.

With increasing ubiquity, wearable technologies are becoming part of everyday life where they may cause controversy, discomfort and social tension. Particularly, body-worn "always-on" cameras raise social acceptability concerns as their form factors hinder bystanders to infer whether they are "in the frame". Screen-based status indicators have been suggested as remedy, but not evaluated in-the-wild. Simultaneously, best practices for evaluating social acceptability in field studies are rare. This work contributes to closing both gaps. First, we contribute results of an in-the-wild evaluation of a screen-based status indicator testing the suitability of the "displayed camera image" design strategy. Second, we discuss methodical implications for evaluating social acceptability in the field, and cover lessons learned from collecting hypersubjective self-reports. We provide a self-critical, in-depth discussion of our field experiment, including study-related behavior patterns, and prototype fidelity. Our work may serve as a reference for field studies evaluating social acceptability.

Sensing interfaces relying on head or facial gestures provide effective solutions for hands-free scenarios. Most of these interfaces utilize sensors attached to the face, as well as into the mouth, being either obtrusive or limited in input bandwidth. In this paper, we propose ChewIt -- a novel intraoral input interface. ChewIt resembles an edible object that allows users to perform various hands-free input operations, both simply and discreetly. Our design is informed by a series of studies investigating the implications of shape, size, locations for comfort, discreetness, maneuverability, and obstructiveness. Additionally, we evaluated potential gestures that users could use to interact with such an intraoral interface.

The use of crowdsourcing platforms for data collection in HCI research is attractive in their ability to provide rapid access to large and diverse participant samples. As a result, several researchers have conducted studies investigating the similarities and differences between data collected through crowdsourcing and more traditional, laboratory-style data collection. We add to this body of research by examining the feasibility of conducting social acceptability studies via crowdsourcing. Social acceptability can be a key determinant for the early adoption of emerging technologies, and as such, we focus our investigation on social acceptability for Head-Worn Display (HWD) input modalities. Our results indicate that data collected via a crowdsourced experiment and a laboratory-style setting did not differ at a statistically significant level. These results provide initial support for crowdsourcing platforms as viable options for conducting social acceptability research.

We propose and explore actuating a smartwatch face to enable extended interactions. Five face movements are defined: rotation, hinging, translation, rising, and orbiting. These movements are incorporated into interaction techniques to address limitations of a fixed watch face. A 20-person study uses concept videos of a passive low fidelity prototype to confirm the usefulness of the actuated interaction techniques. A second 20-person study uses 3D rendered animations to access social acceptability and perceived comfort for different actuation dynamics and usage contexts. Finally, we present Cito, a high-fidelity proof-of-concept hardware prototype that investigates technical challenges.

Innovations often trigger objections before becoming widely accepted. This paper assesses whether a familiarisation over time can be expected for data glasses, too. While user attitudes towards those devices have been reported to be prevalently negative [14], it is still unclear, to what extent this initial, negative user attitude might impede adoption. However, indepth understanding is crucial for reducing barriers early in order to gain access to potential benefits from the technology. With this paper we contribute to a better understanding of factors affecting data glasses adoption, as well as current trends and opinions. Our multiple-year case study (N=118) shows, against expectations, no significant change towards a more positive attitude between 2014 and 2016. We complement these findings with an expert survey (N=51) investigating prognoses, challenges and discussing the relevance of social acceptability. We elicit and contrast a controversial spectrum of expert opinions, and assess whether initial objections can be overwritten. Our analysis shows that while social acceptability is considered relevant for the time being, utility and usability are more valued for long-term adoption.

Smart glasses suffer from obtrusive or cumbersome interaction techniques. Studies show that people are not willing to publicly use, for example, voice control or mid-air gestures in front of the face. Some techniques also hamper the high degree of freedom of the glasses. In this paper, we derive design principles for socially acceptable, yet versatile, interaction techniques for smart glasses based on a survey of related work. We propose an exemplary design, based on a haptic glove integrated with smart glasses, as an embodiment of the design principles. The design is further refined into three interaction scenarios: text entry, scrolling, and point-and-select. Through a user study conducted in a public space we show that the interaction technique is considered unobtrusive and socially acceptable. Furthermore, the performance of the technique in text entry is comparable to state-of-the-art techniques. We conclude by reflecting on the advantages of the proposed design.

The factors affecting the social acceptability of wearable devices are not well understood, yet they have a strong influence on whether a new wearable succeeds or fails. Factors uniquely affecting wearable acceptability as compared to other technology include manners, moral codes, the symbolic communication of dress, habits of dress, fashion, context of use, form, and aesthetics. This paper describes the development of the WEarable Acceptability Range (WEAR Scale), designed to predict acceptance of a particular wearable. First, the construct "social acceptability of a wearable" was defined using literature and an interview study. Second, the WEAR Scale's item pool was composed, and reviewed by experts. Third, the resulting scale was administered to sample respondents along with validation measures. The data will be evaluated for reliability and validity, and the scale's length will be adjusted, culminating in a validated WEAR Scale useful to both industry and academia.

Wearable computing devices offer new possibilities to increase accessibility and independence for individuals with disabilities. However, the adoption of such devices may be influenced by social factors, and useful devices may not be adopted if they are considered inappropriate to use. While public policy may adapt to support accommodations for assistive technology, emerging technologies may be unfamiliar or unaccepted by bystanders. We surveyed 1200 individuals about the use of a head-mounted display in a public setting, examining how information about the user's disability affected judgments of the social acceptability of the scenario. Our findings reveal that observers considered head-mounted display use more socially acceptable if the device was being used to support a person with a disability.

Current uses of smartwatches are focused solely around the wearer's content, viewed by the wearer alone. When worn on a wrist, however, watches are often visible to many other people, making it easy to quickly glance at their displays. We explore the possibility of extending smartwatch interactions to turn personal wearables into more public displays. We begin opening up this area by investigating fundamental aspects of this interaction form, such as the social acceptability and noticeability of looking at someone else's watch, as well as the likelihood of a watch face being visible to others. We then sketch out interaction dimensions as a design space, evaluating each aspect via a web-based study and a deployment of three potential designs. We conclude with a discussion of the findings, implications of the approach and ways in which designers in this space can approach public wrist-worn wearables.

Smart glasses, such as Google Glass, provide always-available displays not offered by console and mobile gaming devices, and could potentially offer a pervasive gaming experience. However, research on input for games on smart glasses has been constrained by the available sensors to date. To help inform design directions, this paper explores user-defined game input for smart glasses beyond the capabilities of current sensors, and focuses on the interaction in public settings. We conducted a user-defined input study with 24 participants, each performing 17 common game control tasks using 3 classes of interaction and 2 form factors of smart glasses, for a total of 2448 trials. Results show that users significantly preferred non-touch and non-handheld interaction over using handheld input devices, such as in-air gestures. Also, for touch input without handheld devices, users preferred interacting with their palms over wearable devices (51% vs 20%). In addition, users preferred interactions that are less noticeable due to concerns with social acceptance, and preferred in-air gestures in front of the torso rather than in front of the face (63% vs 37%).

We propose iSkin, a novel class of skin-worn sensors for touch input on the body. iSkin is a very thin sensor overlay, made of biocompatible materials, and is flexible and stretchable. It can be produced in different shapes and sizes to suit various locations of the body such as the finger, forearm, or ear. Integrating capacitive and resistive touch sensing, the sensor is capable of detecting touch input with two levels of pressure, even when stretched by 30% or when bent with a radius of 0.5cm. Furthermore, iSkin supports single or multiple touch areas of custom shape and arrangement, as well as more complex widgets, such as sliders and click wheels. Recognizing the social importance of skin, we show visual design patterns to customize functional touch sensors and allow for a visually aesthetic appearance. Taken together, these contributions enable new types of on-body devices. This includes finger-worn devices, extensions to conventional wearable devices, and touch input stickers, all fostering direct, quick, and discreet input for mobile computing.

We propose the use of Hand-to-Face input, a method to interact with head-worn displays (HWDs) that involves contact with the face. We explore Hand-to-Face interaction to find suitable techniques for common mobile tasks. We evaluate this form of interaction with document navigation tasks and examine its social acceptability. In a first study, users identify the cheek and forehead as predominant areas for interaction and agree on gestures for tasks involving continuous input, such as document navigation. These results guide the design of several Hand-to-Face navigation techniques and reveal that gestures performed on the cheek are more efficient and less tiring than interactions directly on the HWD. Initial results on the social acceptability of Hand-to-Face input allow us to further refine our design choices, and reveal unforeseen results: some gestures are considered culturally inappropriate and gender plays a role in selection of specific Hand-to-Face interactions. From our overall results, we provide a set of guidelines for developing effective Hand-to-Face interaction techniques.

This paper contributes results from an empirical study of on-skin input, an emerging technique for controlling mobile devices. Skin is fundamentally different from off-body touch surfaces, opening up a new and largely unexplored interaction space. We investigate characteristics of the various skin-specific input modalities, analyze what kinds of gestures are performed on skin, and study what are preferred input locations. Our main findings show that (1) users intuitively leverage the properties of skin for a wide range of more expressive commands than on conventional touch surfaces; (2) established multi-touch gestures can be transferred to on-skin input; (3) physically uncomfortable modalities are deliberately used for irreversible commands and expressing negative emotions; and (4) the forearm and the hand are the most preferred locations on the upper limb for on-skin input. We detail on users' mental models and contribute a first consolidated set of on-skin gestures. Our findings provide guidance for developers of future sensors as well as for designers of future applications of on-skin input.

Ubiquitous Shortcuts is an image processing based method for making and using mnemonics set onto the real world using smartphones or other computing systems. The mnemonics can be created by taking photos of the user's vicinity and by binding them onto command sequences. The mnemonic is triggered every time a similar photo is taken. Our method uses natural feature matching algorithms and end-user programming approaches. The mnemonics can be concatenated into more complex command sequences. Thus, limited user input is realized by just taking photos with a camera embedded into a finger-ring, which enables rapid, subtle and socially acceptable user interaction. Our method can be used as semi-automatic way of achieving location and context sensitive services, activity recognition or tangible interaction.

When the user is engaged with a real-world task it can be inappropriate or difficult to use a smartphone. To address this concern, we developed ShoeSense, a wearable system consisting in part of a shoe-mounted depth sensor pointing upward at the wearer. ShoeSense recognizes relaxed and discreet as well as large and demonstrative hand gestures. In particular, we designed three gesture sets (Triangle, Radial, and Finger-Count) for this setup, which can be performed without visual attention. The advantages of ShoeSense are illustrated in five scenarios: (1) quickly performing frequent operations without reaching for the phone, (2) discreetly performing operations without disturbing others, (3) enhancing operations on mobile devices, (4) supporting accessibility, and (5) artistic performances. We present a proof-of-concept, wearable implementation based on a depth camera and report on a lab study comparing social acceptability, physical and mental demand, and user preference. A second study demonstrates a 94-99% recognition rate of our recognizers.

We present Pinstripe, a textile user interface element for eyes-free, continuous value input on smart garments that uses pinching and rolling a piece of cloth between your fingers. The input granularity can be controlled in a natural way by varying the amount of cloth pinched. Pinstripe input elements physically consist of fields of parallel conductive lines sewn onto the fabric. This way, they can be invisible, and can be included across large areas of a garment. Pinstripe also addresses several problems previously identified in the placement and operation of textile UI elements on smart clothing. Two user studies evaluate ideal placement and orientation of Pinstripe elements on the users' garments as well as acceptance and perceived ease of use of this novel textile input technique.

We present the development of a socially acceptable cueing device for drooling in Parkinson's disease (PD). Sialorrhea, or drooling, is a significant problem associated with PD and has a strong negative emotional impact on those who experience it. Previous studies have shown the potential for managing drooling by using a cueing device. However, the devices used in these studies were deemed unacceptable by their users due to factors such as hearing impairment and social embarrassment. We conducted exploratory scoping work and high fidelity iterative prototyping with people with PD to get their input on the design of a cueing aid and this has given us an insight into challenges that confront users with PD and limit device usability and acceptability. The key finding from working with people with PD was the need for the device to be socially acceptable.

Few research studies focus on how the use of assistive technologies is affected by social interaction among people. We present an interview study of 20 individuals to determine how assistive technology use is affected by social and professional contexts and interactions. We found that specific assistive devices sometimes marked their users as having disabilities; that functional access took priority over feeling self-conscious when using assistive technologies; and that two misperceptions pervaded assistive technology use: (1) that assistive devices could functionally eliminate a disability, and (2) that people with disabilities would be helpless without their devices. Our findings provide further evidence that accessibility should be built into mainstream technologies. When this is not feasible, assistive devices should incorporate cutting edge technologies and strive to be designed for social acceptability, a new design approach we propose here.

The use of performance as the focus of interaction provides the opportunity for exploratory and individual experiences but can also put users in an uncomfortable position. This paper presents an initial user study of a mobile remote awareness application in which users can control their own fish in a virtual fish tank using multimodal input from an external sensing device, where the input styles are created and performed by participants in an open ended sensing model. The study was designed in order to better understand the issues of performance when audience members are both casual passersby and familiar others watching remotely. Additionally, this study investigated the creation of performances and the effects of props when used in different social settings. The study involved pairs of participants interacting with the system in both public and private locations over repeated sessions. The results of this study show how users created and interpreted performances as well as how their consideration of passersby influenced their experiences.

Gesture-based mobile interfaces require users to change the way they use technology in public settings. Since mobile phones are part of our public appearance, designers must integrate gestures that users perceive as acceptable for pub-lic use. This topic has received little attention in the litera-ture so far. The studies described in this paper begin to look at the social acceptability of a set of gestures with re-spect to location and audience in order to investigate possi-ble ways of measuring social acceptability. The results of the initial survey showed that location and audience had a significant impact on a user's willingness to perform ges-tures. These results were further examined through a user study where participants were asked to perform gestures in different settings (including a busy street) over repeated trials. The results of this work provide gesture design rec-ommendations as well as social acceptability evaluation guidelines.