A GPS tracking device uses Global Positioning System and determines the exact location of a vehicle or any other object that is attached to it. The recorded data is first stored in the GPS tracking unit and then transmitted to a database using a modem embedded in the unit. After this, the location is displayed in real time (or can be viewed later) against a map backdrop. For instance, a GPS phone tracker is used to locate your lost smartphone, when you accidentally lose it or when it gets stolen. Similarly, GPS vehicle tracking is useful in more ways than one.