[mcmillion]

Yes. Anything less than this becomes perceptible and starts to make the UX feel janky or sluggish. That is a huge turn-off for a lot of users, even if they can't pin down the exact cause being low framerate.

And framerate in UI is a different beast compared to video. A menu animation running at 24fps feels much choppier and sluggish than a video running at 24fps.

[teamhappy]

No. The amount of fames you need depends on the distance an object moves per frame.

I really don't want to argue about this so I figured I just let you experience it yourself: http://jsbin.com/qizatugepo/1/edit?js,output

Frame drops are a different story entirely. The swap_control_tear extension for OpenGL takes care of that to some degree though.

[MrScruff]

Typically in a mobile app I'm flick scrolling at speed through lists. So the maximum distance travelled per frame is pretty high.