With Unity, I used the prefabs OVRPlayerController and LocalAvatar. The hand avatars and the controllers appear upon start of the app (* after configuring the app ID in both required locations).
But after a few seconds, geometry rendering quickly deteriorates, which looks very unusual (see photos / video here).
Occurs with Oculus integration 1.38, 1.39, 1.40 and Unity 2018.4.8 and 2919.2.
The oculus home environment or other apps render as normal.
Solution: The Unity shader deteriorate if the player controller is in free-fall due to gravity (floating point issue in shader). The solution therefore is to put some ground gameobject (i.e. plane) under the player controller.