User Experiences in ThrowIt: A Natural UI for Sharing Objects between Mobile Devices

The success of context-aware systems depends on intuitive user interface designs which facilitate communication between multiple devices. This paper presents Throw It, a natural user interface for sharing objects between mobile devices using gaze and hand gestures. For enabling gesture control, Throw It includes an off-the-shelf monochrome camera with infrared lights and a hand-held 6 degree of freedom sensor. To share an object, the user first locks their gaze on the object, then selects the object by doing a short ´grab´ gesture, and finally, sends the object to another mobile device by doing a ´throwing´ gesture. The mobile devices locate each other via a context server. According to the results of our user study, the idea of sharing digital objects using Throw It was found both useful and fascinating. However, sharing objects to many people at the same time raised security concerns.