Here is a discreet GPS tracker that lets you monitor the location of your car on your smartphone. The ShieldGPS connects to your car’s OBD-II port and is tiny enough not to raise any suspicion. It allows vehicle tracking on iOS, Android, and internet connected devices.
The device sends location updates every 10 seconds. You can create geofences to get alerted when your vehicle enters or exits and area. Speed alerts are also supported.