Sharing Touch Interfaces: Proximity-Sensitive Touch Targets for Tablet-Mediated Collaboration

During conversational practices, such as a tablet-mediated sales conversation between a salesperson and a customer, tablets are often used by two users who prefer specific bodily formations in order to easily face each other and the surface of the touchscreen. In a series of studies, we investigated bodily formations that are preferred during tablet-mediated sales conversations, and explored the effect of these formations on performance in acquiring touch targets (e.g., buttons) on a tablet device. We found that bodily formations cause decreased viewing angles to the shared screen, which results in a decreased performance in target acquisition. In order to address this issue, a multi-modal design consideration is presented, which combines mid-air finger movement and touch into a unified input modality, allowing the design of proximity sensitive touch targets. We conclude that the proposed embodied interaction design not only has potential to improve targeting performance, but also adapts the ``agency' of touch targets for multi-user settings.