With the DroidDrone you can easily control your INAV, ArduPilot or Betaflight drone via the Internet. You only need two Android phones - one is on the drone and connects to the flight controller with the OTG USB and the other connects to your remote controller.
DroidDrone is a free open source project. Visit our GitHub page for more info:
https://github.com/DroidDrone/DroidDrone