A Comparative Study on Inter-Device Interaction: One-Handed Interaction VS Two-Handed Interaction

Using mobile devices to collaborate with other users on a large shared screen supports collaborative tasks and prevents interference among users. Various intuitive gestures have been proposed to support interaction across a tabletop and a mobile device. Different from previous studies that focused on designing gestures, this paper investigates the fundamental difference between one-handed and two-handed interaction styles that involve a tabletop and a mobile device. In the study, we consider two factors, i.e., the selection order (sequential or random order) and the density level (sparse or dense layout), which form four tasks. The study was conducted as a pretest-posttest, repeated-measures experiment. All the participants go through all the tasks using both interaction styles. During the experiment, both the completion time and the error rate in each task with each interaction style are recorded. In addition, the IBM Post-Study Usability Questionnaire (PSSUQ) is used to evaluate the subjective satisfaction on each interaction style. The overall PSSUQ score indicates that both interaction styles receive positive feedback with high user satisfaction. The one-handed interaction is significantly more efficient than the two-handed interaction in all four tasks. On the other hand, the two-handed interaction has a lower error rate than the one-handed interaction, especially significantly lower in a dense layout.