Hi,
I have wrote an autosteering/autopilot software for special agriculture machines (similar like tractors) based on Arduinos. I use an iPad for the display.
I have made some test videos about the accuracy.
Straight line test with autopilot:
Curved line test with autopilot:
Display tests -compare with JD Greenstar 2630
Please note that, for this project any antenna/receiver with RTK (providing standard GPS sentences) still required. In my case I am using an John Deere Starfire 3000.
Szotyi