Phase alternating from stationary to moved = no good

I’m trying to do a flick scroll, I manage to scroll by touch but I’m having no luck doing the deceleration on release because it keeps returning stationaries.

It seems that the same fingerID phase alternates between Moved to Stationary, which makes me wonder how I detect finger movement on the iphone

any idea?

You could check how far you moved since the beginning of the movement, by just using the begin and end phase.