[Terr_]

Probably the acceleration vector. If the phone is rapidly moved a meter away from you, either it's being snatched or it's being thrown.

Edit: To clarify, I was thinking of horizontally, in the direction that corresponds to the top of the screen, as if you were bent over using the phone--probably holding the bottom-of-screen--and then someone grabbed the top-of-screen to pull it away.

[curiousObject]

> If the phone is rapidly moved a meter away from you, either it's being snatched or it's being thrown.

Good heuristics. Also that must not be a mainly downward rapid movement, which probably only means you just dropped your phone.

[jimbobthrowawy]

A drop registers as no acceleration while in freefall, and then a sharp spike when it hits the ground. This was counter-intuitive to me when I first figured out how to display my phone's accelerometer readouts, but makes sense.

[Terr_]

I think a lot of the false-positive cases where the screen gets locked are acceptable in context.

I mean, most people dropping their phone will be too glad/devastated that the device did/didn't escape harm to bother being annoyed that they have to unlock the screen again.