When doing exercises like the Wall Pec stretch or Kneeling squad stretch where there’s:
  1. 10 sec ready for one side
  2. Count down for one side
  3. 10 sec ready for other side
  4. Count down for other side
If the iPhone screen is off. The 10 sec ready for the other side (3) never finishes. So we can’t leave the phone screen off when we those sort of exercises
Works fine if iPhone screen is on