Jonna Häkkilä

Tap input as an embedded interaction method for mobile devices

In this paper we describe a novel interaction method for interacting with mobile devices without the need to access a keypad or a display. A tap with a hand can be reliably detected e.g. through a pocket by means of an acceleration sensor. By carefully designing the user interface, the tap can be used to activate logically similar functionalities on the device, leading to a simple but useful interaction method. We present results of user tests aimed at studying the usability of various tap input based user interface applications.

Utilising context ontology in mobile device application personalisation

Context Studio, an application personalisation tool for semi-automated context-based adaptation, has been proposed to provide a flexible means of implementing context-aware features. In this paper, Context Studio is further developed for the end users of small-screen mobile devices. Navigating and information presentation are designed for small screens, especially for the Series 60 mobile phone user interface. Context ontology, with an enhanced vocabulary model, is utilized to offer scalable representation and easy navigation of context and action information in the UI. The ontology vocabulary hierarchy is transformed into a folder-file model representation in the graphical user interface. UI elements can be directly updated, according to the extensions and modifications to ontology vocabularies, automatically in an online system. A rule model is utilized to allow systematic management and presentation of context-action rules in the user interface. The chosen ontology-based UI model is evaluated with a usability study.

Mobile interaction with visual and RFID tags: a field study on user perceptions

In this paper, we present a study of user perceptions on mobile interaction with visual and RFID tags. Although mobile interaction with tags has been proposed in several earlier studies, user perceptions and usability comparisons of different tag technologies have not been intensively investigated. In contrast to earlier studies, which report on user studies with evaluating new concepts or interaction techniques, we take another approach and examine the current understanding of the techniques and user perceptions on them. Our field study of 50 users charts currently existing user perceptions and reveals potential usability risks that are due to the limited or erroneous understanding of the interaction technique.

Evaluating capacitive touch input on clothes

Wearable computing and smart clothing have attracted a lot of attention in the last years. For a variety of applications, it can be seen as potential future direction of mobile user interfaces. In this paper, we concentrate on usability and applicability issues concerned with capacitive touch input on clothing. To be able to perform user studies, we built a generic platform for attaching, e.g., capacitive sensors of different types. On top of that, several prototypes of wearable accessories and clothing and implemented various application scenarios. We report on two studies we undertook with these implementations with a user group randomly sampled at a shopping mall. We provide a significant set of guidelines and lessons learned that emerged from our experiences and those studies. Thus, developers of similar projects have to put major efforts into minimizing the delay between button activation and feedback and to make location and identification of controls and their function as simple and quick as possible. Issues that have to be treated in all designs include the requirement of one-handed interaction and that, even for minimal functionality, to find a general solution with regard to layout and button-to-function mapping is hardly possible. Additionally, in order to generate a satisfactory user experience good usability must be combined with aesthetical factors.

On-line personalization of a touch screen based keyboard

The user expectations for usability and personalization along with decreasing size of handheld devices challenge traditional keypad layout design. We have developed a method for on-line adaptation of a touch pad keyboard layout. The method starts from an original layout and monitors the usage of the keyboard by recording and analyzing the keystrokes. An on-line learning algorithm subtly moves the keys according to the spatial distribution of keystrokes. In consequence, the keyboard matches better to the users physical extensions and grasp of the device, and makes the physical trajectories during typing more comfortable. We present two implementations that apply different vector quantization algorithms to produce an adaptive keyboard with visual on-line feedback. Both qualitative and quantitative results show that the changes in the keyboard are consistent, and related to the users handedness and hand extensions. The testees found the on-line personalization positive. The method can either be applied for on-line personalization of keyboards or for ergonomics research

Let's all get up and walk to the North Pole: design and evaluation of a mobile wellness application

Mobile wellness applications can motivate people to exercise more because of their ubiquitous presence and suitable technological possibilities. Wellness applications utilize several factors that can increase physical activity levels of users, e.g., data tracking, social sharing and playfulness. We describe the design and evaluation of a mobile-phone based wellness application addressing social sharing and playfulness. In our user study with 37 participants we focus on presentation of physical activity data as a virtual trip on a map-based game world. The findings reveal design implications that support users to be motivated in doing the physical exercise, including setting departure and destination places and viewing up-to-date progress between them. The virtual trip was considered an understandable, concrete and interesting analogy. The familiarity of the map of the home country as the game world was liked because it added concreteness and understandability to the achievements.

Developing design guidelines for context-aware mobile applications

Context-aware computing sets new challenges for interaction design. This paper introduces the special characteristics of context-aware mobile devices that should be taken into account in interaction and user interface design, and proposes design guidelines for context-aware mobile applications. The proposed guidelines are evaluated with two design exercises.

Collaboration in Context-Aware Mobile Phone Applications

Context-aware applications are expected to become a remarkable application area within future mobile computing. As mobile phones form a natural tool for interaction between people, the influence of the current context on collaboration is desirable to take into account to enhance the efficiency and quality of the interaction. This paper presents role of context information in improving the collaboration of mobile communication by supplying relevant information to the cooperating parties, one being a mobile terminal user and the other either another person, group of people, or a mobile service provider.

Towards designing better maps for indoor navigation: experiences from a case study

Recent development in indoor navigation systems and related studies imply that these applications will become common in the future. A variety of solutions utilizing different mediums is being developed. Lately, a range of mobile devices have started to support outdoor pedestrian navigation, and these devices presumably keep guiding the users also when moving indoors. However, the design patterns from the outdoor world do not necessarily work indoors. In order to understand the distinctive UI requirements of indoor navigation, we conducted a user study involving 23 people using a mobile phone-based, location-sensitive service. In this paper, we reveal our findings that the visualizations and UI designs resembling conventional outdoor maps or floor layouts are not optimal for indoor navigation, and present recommendations for the future design of indoor navigation systems.

Tracking Outdoor Sports --- User Experience Perspective

In this paper, the potential role of a sport tracking application is examined in the context of supporting tracking outdoor sporting activities. A user study with 28 participants was conducted to study the usage habits and user experiences evoked. The application consists of a mobile tracking tool and a related web service. It collects and stores workout data such as the route, speed and time, and compiles a training diary that can be viewed in many ways during the exercise and afterwards. Data can be uploaded into a web service for further analysis or for sharing it with others. The results show high interest in tracking outdoor sports with a mobile phone application --- the participants used the application during almost all exercise sessions and stated that they would continue using the application after the study. Sharing data was not perceived as valuable, although some usage scenarios for social sharing arose.