Focus+context visualization techniques for displaying large lists with multiple points of interest on small tactile screens

Abstract. This paper presents a focus+context visualization and interaction technique for displaying large lists on handheld devices. This technique has been specifically designed to fit the constraints of small tactile screens. Thanks to its spiral layout, it provides a global view of large lists on a limited amount of screen real-estate. It has also been designed to allow direct interaction with fingers. This technique proposes an alternative to multi-focus visualization, called “augmented context”, where several objects of interest can be pointed up simultaneously. We propose two implementations of this approach that either use spatial or temporal composition. We conducted a controlled experiment that compares our approach to standard scrollable lists for a search task on a PDA phone. Results show that our technique significantly reduces the error rate (about 3.7 times lower) without loss of performance

ThumbSpace: generalized one-handed input for touchscreen-based mobile devices

Abstract. In this paper, we present ThumbSpace, a software-based interaction technique that provides general one-handed thumb operation of touchscreenbased mobile devices. Our goals are to provide controlled and accurate selection of all interface objects, especially small and far targets, which are traditionally difficult to interact with using the thumb. ThumbSpace is designed to provide these benefits independent of the application design, which can free designers to focus on effective presentation, as well as efficient interaction when two hands are available. We present the ThumbSpace design and a comparative evaluation against direct interaction for target selection. Our results show that in addition to being well received, ThumbSpace improves accuracy for selecting targets that are out of thumb reach, and makes users as effective at selecting small targets as large targets. The results further suggest user practice and strategic design iterations hold potential to close the gap in access time between the two input methods, where ThumbSpace does not do as well as direct interactions