Is it fine if I leave the device plugged in to my car? Will it drain my battery?

The Engie device consumes minimal power, much like a vehicle's alarm. Therefore, while the vehicle is on or off you can leave the device connected.

By keeping the device connected at all times, you will be able to constantly track the vehicle's data. The Engie device uses around (40 mAh), similar to a headset or vehicle alarm. Therefore, leaving the device plugged in does not affect the battery.