i have been using back tap since 13pro, i have set double tap to screen lock and triple tap to Screenshot, since then i have moved to 15pro and still have same issues with back tap as were in 13pro.

some times it works as intented on Gentle taps, sometimes hitting reasonably hard enough also doesn’t trigger the functions, sometimes gently keep phone on desk triggers triple tap. i haven’t found a consistent way of making it work.

i have tapped on regions above Apple logo and on apple logo. Tapping on corner of camera island works the most of the time but still inconsistent