Mobile interaction can potentially be enhanced with welldesigned haptic control and display. However, advances have been limited by a vicious cycle whereby inadequate haptic technology obstructs inception of vitalizing applications. We present the first stages of a systematic design effort to break that cycle, beginning with specific usage scenarios and a new handheld display platform based on lateral skin stretch. Results of a perceptual device characterization inform mappings between device capabilities and specific roles in mobile interaction, and the next step of hardware re-engineering. Author Keywords Mobile, haptic, tactile, handheld interaction, multimodal, display, design process, lateral skin stretch

Acontextuality of the mobile phone often leads to a caller's uncertainty over a callee's current state, which in turn often hampers mobile collaboration. We are interested in re-designing a Smartphone's contact book to provide cues of the current situations of others. ContextContacts presents several meaningful, automatically communicated situation cues of trusted others. Its interaction design follows social psychological findings on how people make social attributions based on impoverished cues, on how self-disclosure of cues is progressively and interactionally managed, and on how mobility affects interaction through cues. We argue how our design choices support mobile communication decisions and group coordinations by promoting awareness. As a result, the design is very minimal and integrated, in an "unremarkable" manner, to previously learned usage patterns with the phone. First laboratory and field evaluations indicate important boundary conditions for and promising avenues toward more useful and enjoyable mobile awareness applications.

baudisch @ microsoft.com Figure 1. Using earPod. (a, b) Sliding the thumb on the circular touchpad allows discovery of menu items; (c) the desired item is selected by lifting the thumb; (d) faster finger motions cause partial playback of audio. Size of the touchpad has been exaggerated for illustration purposes. We present the design and evaluation of earPod: an eyesfree menu technique using touch input and reactive auditory feedback. Studies comparing earPod with an iPod-like visual menu technique on reasonably-sized static menus indicate that they are comparable in accuracy. In terms of efficiency (speed), earPod is initially slower, but outperforms the visual technique within 30 minutes of practice. Our results indicate that earPod is potentially a reasonable eyesfree menu technique for general use, and is a particularly exciting technique for use in mobile device interfaces. ACM Classification: H5.2 [Information interfaces and presentation]: User Interfaces. Input devices and strategies;

Camera phones have been viewed simplistically as digital cameras with poor picture quality while neglecting the utility of the two key functionalities of mobile phones: network connection and access to personal information. This is the first HCI paper to examine mobile photos from a systemic perspective: how assignment of phases of mobile photo lifecycle to different platforms affects social discourse around shared photos. We conducted a 6-week user trial of MobShare, a tripartite system with dedicated functions and task couplings for a mobile phone, a server, and a PC browser. We analyze how MobShare’s couplings and distribution of functionalities affected the observed types of social discourse that formed around mobile photos: in-group post-event discourse, self-documents and reports, greetings and thanks. Several central design issues arising from the systemic view are discussed: heterogeneity of environments, integration and distribution of functionalities, couplings and decouplings of interaction tasks, notification mechanisms, and provision of necessary UI resources for different tasks.

Adding expressive haptic feedback to mobile devices has great potential to improve their usability, particularly in multitasking situations where one’s visual attention is required. Piezoelectric actuators are emerging as one suitable technology for rendering expressive haptic feedback on mobile devices. We describe the design of redundant piezoelectric haptic augmentations of touchscreen GUI buttons, progress bars, and scroll bars, and their evaluation under varying cognitive load. Our haptically augmented progress bars and scroll bars led to significantly faster task completion, and favourable subjective reactions. We further discuss resulting insights into designing useful haptic feedback for touchscreens and highlight challenges, including means of enhancing usability, types of interactions where value is maximized, difficulty in disambiguating background from foreground signals, tradeoffs in haptic strength vs. resolution, and subtleties in evaluating these types of interactions. Categories and Subject Descriptors H5.2 [Information interfaces and presentation]: User Interfaces- graphical user interfaces, haptic I/O. (e.g., library, business meeting). In addition, mobile devices are often used while the user is performing some other task (looking up online information during a presentation as in Figure 1, or using a map on a mobile device while walking down a busy sidewalk), and these tasks compete for the user’s cognitive resources [11]. Adding another interface modality, such as haptic feedback, allows more channels for a mobile device to communicate with its user. Mobile devices are especially suitable for haptic feedback as these devices are often held by the user or carried in close bodily contact.

Visual information overload is a threat to the interpretation of displays presenting large data sets or complex application environments. To combat this problem, researchers have begun to explore how haptic feedback can be used as another means for information transmission. In this paper, we show that people can perceive and accurately process haptically rendered ordinal data while under cognitive workload. We evaluate three haptic models for rendering ordinal data with participants who were performing a taxing visual tracking task. The evaluation demonstrates that information rendered by these models is perceptually available even when users are visually busy. This preliminary research has promising implications for haptic augmentation of visual displays for information visualization.

Adaptive personalization, where the system adapts the interface to a user’s needs, has the potential for significant performance benefits on small screen devices. However, research on adaptive interfaces has almost exclusively focused on desktop displays. To explore how well previous findings generalize to small screen devices, we conducted a study with 36 subjects to compare adaptive interfaces for small and desktop-sized screens. Results show that high accuracy adaptive menus have an even larger positive impact on performance and satisfaction when screen real estate is constrained. The drawback of the high accuracy menus, however, is that they reduce the user’s awareness of the full set of items in the interface, potentially making it more difficult for users to learn about new features. Author Keywords Adaptive interfaces, personalization, small screen devices, menu design, user study, interaction techniques. ACM Classification Keywords H.5.2 [User Interfaces]: Evaluation/methodology, interaction styles.

Haptic icons (brief tactile stimuli with associated meanings) have the potential to convey abstract information through touch; however, there has been little systematic investigation of how sets of perceptually distinct tactile signals can be best utilized to convey meanings, nor of how enduring these associations can be. We hypothesized that when users can choose the signals which will represent specific concepts, their learning and recall will be eased and enhanced. Taking future embedded interfaces as context, we used two sets of 10 distinct tactile signals to compare recall of concept-meaning associations in two conditions: (1) arbitrarily assigned and (2) participant-chosen associations. Participants learned associations in under 20 minutes at 80% accuracy; at 2 weeks, recall of the associations previously learned was 86 % with no significant effect of assignment condition. Subjective confidence levels sharply lagged actual performance, with zero expectation of ability to recall at 2 weeks. To the best of our knowledge, this is the first study of either longitudinal recall or the role of user choice on synthesized stimulus-meaning learnability. Its results underscore the eminent practicality of using haptic icons in everyday interface design, suggesting high learnability and a surprising user ability to find their own mnemonics for carefully composed stimuli, regardless of how associations are assigned.

To fully appreciate the opportunities provided by interactive and ubiquitous multimedia to record and share experiences, we report on an ethnographic investigation on the settings and nature of human memory and experience at a large-scale event. We studied two groups of spectators at a FIA World Rally Championship in Finland, both equipped with multimedia mobile phones. Our analysis of the organization of experience-related activities in the mass event focuses on the active role of technology-mediated memories in constructing experiences. Continuity, reflexivity in regard to the Self and the group, maintaining and re-creating group identity, protagonism and active spectatorship were important social aspects of the experience and were directly reflected in how multimedia was used. Particularly, we witnessed multimedia-mediated forms of expression such as staging, competition, storytelling, joking, communicating presence, and portraying others; and the motivation for these stemmed from the engaging, processual, and shared nature of experience. Moreover, we observed how temporality and spatiality provided a platform for constructing experiences. The analysis advocates applications that not only store or capture human experience for sharing or later use but also actively participates in the very construction of experience. The approach conveys several valuable design implications. Large-scale events, ethnographic field study, sharing experiences, constructive memory, mobile and ubiquitous multimedia, active spectators 1

When browsing Web pages with a mobile device, the system response times are variable and much longer than on a PC. Users must repeatedly glance at the display to see when the page finally arrives, although mobility demands a Minimal Attention User Interface. We conducted a user study with 27 participants to discover the point at which visual feedback stops reaching the user in mobile context. In the study, we examined the deployment of attention during page loading to the phone vs. the environment in several different everyday mobility contexts, and compared these to the laboratory context. The first part of the page appeared on the screen typically in 11 seconds, but we found that the user's visual attention shifted away from the mobile browser usually between 4 and 8 seconds in the mobile context. In contrast, the continuous span of attention to the browser was more than 14 seconds in the laboratory condition. Based on our study results, we recommend mobile applications provide multimodal feedback for delays of more than four seconds.