I just returned from a cross country flight and had a similar problem. Pixel 5A phone. Recently updated to Android 12. I think it worked well on the flight out Wednesday, but on the return leg today, the iFly app reported weak GPS reception. The plane icon appeared to be tracking my flight but it never turned off of North to show my direction of flight. Strange. I closed the app and restarted - same problem. Upon landing I restarted the app again and had the same problem. Google map would properly show my direction and speed when the iFly app would not. Verified permissons for GPS access for the iFly app. The panel mounted 740b never missed a beat.
Best, John