Cearch is a tracking service developed by Telcordia Technologies and Norbelle. The application can be used on mobile devices to track tags(physical devices attached to the intended target) or other mobile devices. By tracking I mean knowing the location, to within 1 meter with an arrow pointing you to that location, speed of the target, and distance of the target to you. The tracking is based on both GPS and trilateral calculations from cell towers of the target's location relative to the tracking device. The tracking device can be a mobile device with the software installed on it or a computer terminal. To be able to track other mobile devices, the tracking software must be installed on that device as well.

They suggest it can be used as a traditional locater for such tasks as finding buildings or directions when lost but where this service is unique is for the ability to bring you so close to your target (single person in a crowd) or the ability to track a moving target (finding a lost person, or a stolen vehicle).

http://www.norbelle.com/cearch.htm