Encounter Bubbles is a visualization tool that enables users to explore their social encounters in new ways. It is built on top of the Mobster (an open framework on which locative networking applications can be built) sociolocative service framework.

The system evolves around the concept of “encounters.” Each encounter consists of two devices, a start time, and an end time. An encounter can be registered when two users (represented by two mobile devices) come within range of one another, or it can be registered between a user (represented by a mobile device) and a place (represented by a stationary device such as a wireless Internet access point).

The user sends its encounter records to the centralized Mobster server application which keeps track of users, places, and encounters. On the server, each place can be “tagged” by users with a place name. Users are recognized by unique identification numbers associated with their devices.

From Cheesebikini , via Pasta and Vinegar.