We noticed that there is a recent iOS bug causing flickering/flashing screen.
To resolve it, here are solutions:
1. Turn your phone off and on.
2. Make sure your iOS and VR app is in the latest version or try to join the Apple beta program
If the issue persists, try another app and turn your phone off and on.
Please kindly note: This VR app flashing screen problem only happens on iOS, while android system doesnt.