If you are looking to further increase your protection, you can simply add a rear camera to most of thinkwares Front facing main units. The rear cam simply fits to your rear window and looks backwards, this plugs into the front unit via the supplied cable (please check unit specs for lead length) and then all footage is recorded on the front cameras Micro SD card.
The GPS signal receiver can be used to keep track of your vehicle’s physical location as you drive. Along with your position, GPS can also keep track of your speed. During video playback, a simultaneous Google map view will show your vehicle moving around, and how fast you were going.