ABSTRACT
Sharing digital documents among multiple users on a large tabletop is one of the typical application scenarios for tabletop systems. In this chapter, we elaborate on the guidelines of designing a user interface for this application scenario. A set of finger gestures are then defined within the interface that includes single finger operation for selecting, moving, and delivering a digital document among multiple users; double finger operation for resizing and rotating a digital document; trajectory operation for creating and deleting a user work area; and creating, deleting, and copying a digital document. A prototype tabletop application called JuTable is developed to explore these gestures. A discussion on learnability, usability, and the naturalness of our interface design for this application scenario is last.
