since I set the MKUserTrackingMode to follow I get this error :
[MKCoreLocationProvider] CLLocationManager(<CLLocationManager: 0x6000003b86d0>) for <MKCoreLocationProvider: 0x6000033b05a0> did fail with error: Error Domain=kCLErrorDomain Code=1 "(null)"
and the map doesn't track the location of the gpx file either.
What can you do there?