Question

On iPad the vmousemove event is triggered even when no move has been performed. Why’s that?

Steps to reproduce:

1. Open http://jsfiddle.net/dcbV7/
2. Tap A div then B. Only tap them, but fast

Result: you see vmousemove event is triggered

Answer 1

vmousemove simulates the movement of a mouse. It would be as if you clicked A div, moved the mouse to B, then clicked it. There would be no other way to get a mouse from one to the other, after all.

If you try this on a device with a mouse, you’ll notice that vmousemove is triggered every time the mouse is actually moved. The best heuristic they have for mouse-less environments is that touching two points close together in a short amount of time is similar to doing the same with a mouse.