I have a BlackVue (can't remember which model) and its great. Very good quality images day and night, it has GPS tracking/ speed readout (optional), time and date stamp. You can connect to it via WiFi or plug the micro SD card into your device.
It's hardwired into the fuse box and will automatically turn off if the voltage on the battery gets to low so it doesn't die. It records when moving and parked and sensors violent movement and the videos are flagged as red, you can also set the sensitivity. Its not cheap, around £300 all in but is very good.