HOW THE DEVICE WORKS:   After easy installation and insertion of a sim card into the GPS & GSM Tracker, you can SMS the device from your mobile phone and the Tracker will send back co-ordinates of your vehicle’s position in real time. This information can then be entered into Google Earth or similar computer program which will then give you the location of your vehicle.   It can be connected with your car alarm system. Provide three sensors trigger signal input to upgrade your original Car Alarm system (like shocking sensor, moving detecting trigger, Urgent help trigger, ACC Trigger and Door Trigger), for example: when someone open your car door, the system will send a message to warn you.