+1. I did add very subtle haptics (possibly too subtle) as the indicator changes, but I like the idea of making them stronger and recognisable for each breath phase
pick up a cheap Fitbit on Amazon, they have a pretty good haptic breathwork flow.
another interesting thought, maybe user could lay down on their back place iPhone on chest, and you can measure breathing with accelerometer? that could be even more accurate than camera + mic
another interesting thought, maybe user could lay down on their back place iPhone on chest, and you can measure breathing with accelerometer? that could be even more accurate than camera + mic