Tabletops incite people to collaborate around shared documents. We propose DIGITABLE, a platform for collocated and remote collaboration which attempts to preserve the fluidity of interactions and the mutual awareness of copresence. DIGITABLE combines a multiuser tactile tabletop, a video-communication system and a robust computer vision module for distant users? gesture visualization.

From an experiment, we show that DIGITABLE improves the efficiency of a collaborative task in remote configuration. We also show that remote gesture visualization facilitates coordination as it provides to local participants important information such as intentionality and pointing. Thus, collocated and remote configurations are both worthwhile experiences: remote collaboration is not seen anymore as a poor ersatz of collocated collaboration, although presence feeling is not uniformly perceived by participants.