The rain stopped so I set up a test in the driveway, marking a single waypoint in the iPad GS app at the place where I was sitting with the Phantom. This is the same place I'd marked earlier with a waypoint in Google Earth, my Garmin, and Motion X.
Driveway: iPad GS, sitting at the waypoint:
122.11274
48.75109
Driveway: iPad GS waypoint placed earlier, at some distance from the actual spot.
122.11273
48.75109
I did a similar comparison with a couple of other waypoints around the property -- again, the difference in coordinates seems very small.
One more wrinkle: the GS app showed the aircraft as 117 feet away when it was actually sitting on the waypoint. When I took my Futaba for a short walk, testing a new fpv antenna, the iOSD Mini also showed me as being 34 meters from the Phantom -- again, when I was actually next to it.
Driveway: iPad GS, sitting at the waypoint:
122.11274
48.75109
Driveway: iPad GS waypoint placed earlier, at some distance from the actual spot.
122.11273
48.75109
I did a similar comparison with a couple of other waypoints around the property -- again, the difference in coordinates seems very small.
One more wrinkle: the GS app showed the aircraft as 117 feet away when it was actually sitting on the waypoint. When I took my Futaba for a short walk, testing a new fpv antenna, the iOSD Mini also showed me as being 34 meters from the Phantom -- again, when I was actually next to it.