I am using the latest version of Collector on a Google Pixel 2 (Android 8.1) and an iPad (wifi version) on iOs 10.4.1. When I use the Garmin Glo external GPS on the Google Pixel 2, Collector reports an accuracy between 5 and 6 feet. If I connect the same Garmin Glo to the iPad at the same time, Collector reports an accuracy on the iPad of 16 feet.
In both instances I know Collector is using the Garmin Glo's position, as I can walk away from the Glo and my position on the map does not change.
So why the difference in reported accuracy between the android and apple devices using the same external GPS?
I'm getting 16.4 ft when paired with an iPad Air 2, iOS 12.1, using Collector whether inside a building or outside with full horizon view. Could this be a memory cache-related error? I don't have an Android device to test it with, but the fact that it doesn't change from indoors to outdoors makes me skeptical of the reading. Good question!
UPDATE: I paired the Garmin GLO with an iPhone 7 running iOS 12.1 and got 28.4 ft (95%). I'm don't know the source of that discrepancy. I have a colleague who also has a GLO but uses Windows and Android platforms, so I asked him to tell me his experiences with those. I'll let you know what he says.
Its been a while, but I recall connecting the Glo to the iPad with just bluetooth. As a white listed apple product, it should overwrite the core location service apple provides to Collector without setting up a location profile. on android, i used the bluetooth GPS app to enable "mock" gps location. again, no location profile setup in collector.