Kaj Makela

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.

Mobile video editor: design and evaluation

Mobile phones have evolved from voice-centric communication devices to powerful personal multimedia devices. Among other multimedia features, they enable the users to capture video clips with built-in digital cameras. However, due to the continuous nature of video, it is often difficult to capture a video clip exactly as intended - in many cases the possibility to edit the clip after capture would be useful. We describe the design of a video editor application for mobile devices. We present the main user goals for video editing in the mobile context based on a Contextual Inquiry study and an application design that supports these goals. We demonstrate that video editing on mobile devices is feasible and report a usability evaluation with encouraging results.

Empirical observations on video editing in the mobile context

Todays mobile devices enable the users to capture video clips with integrated digital cameras. However, capturing a video clip exactly as intended is often challenging -- in many cases, the possibility to edit the clip after capture would be useful. Earlier we have presented the Mobile Video Editor, an application that allows the users to edit video clips instantly after capture on their mobile devices. In this paper, we describe a field trial that we arranged to further evaluate the Mobile Video Editor concept and to better understand the usage patterns of video editing in the mobile context. The results indicate that especially the teenagers and younger adults found the capability to edit captured video clips a beneficial feature in mobile devices. In addition to being a practical tool to prepare the videos for sharing with others, the Mobile Video Editor was used as a form of entertainment.