"GPS (Global Positioning Satellite) trackers use signals from satellites to calculate their exact location. These locations are incredibly accurate (easily averaging 2-10 meters accuracy). The trackers need mobile phone signal (GSM/GPRS) to be able to report their location to a mapping website or in the case of a text tracker to a mobile phone. All of our trackers are quad band and operate worldwide wherever there is GSM network. Please use this link to see a map of global GSM coverage.  Do not confuse GPS trackers with GSM trackers which use triangulation from mobile phone masts to estimate a location. Their accuracy can sometimes be to within a mile or more.
Text trackers operate by being phoned by any mobile phone, the tracker calculates its location and then replies via text message with its longitude and latitude co-ordinates. The user then enters these co-ordinates into the "find" field of any mapping website such as Google Maps or Google earth. Some Sat-nav systems are also capable of such use.
Our more sophisticated “live” trackers record their locations within their memory and report (at various user defined periods) to our own mapping website via GPRS (part of the GSM phone network). By logging on to this website the trackers exact, moving location can be seen.
(Click on the image to see mapping examples) | 
