How the cops watch your tweets in real-time

BlueJay allows users to enter a set of Twitter accounts, keywords, and locations to scan for within 25-mile geofences (BlueJay users can create up to five such fences), then it returns all matching tweets in real-time. If the tweets come with GPS locations, they are plotted on a map. The product can also export databases of up to 100,000 matching tweets at a time.

BrightPlanet also offers GeoTime, a separate data visualization tool that can take exported BlueJay data and mine it to show where and when the target travels, what he tweets about at various locations, and where his phone resides at night.