Video Overlay does not line up with track?

[Boozshey]

I am using an iPhone 7 with a SkyPro XGPS160 GPS Receiver. When I import the data into a mapping image it shows that it's off track. This has also showed that my distance traveled is extremely long compare to the length of the track.

Are the map overlays suppose to be more accurate than this?

[Harry]

That's the so called GPS drift. If not compensated by some augmentation system, you will have a time and location dependent offset between actual location and location reported. This doesn't hurt timing accuracy a lot, but makes it difficult to analyse the line driven.

- Harry