iphone/ipad large canvas vs small canvas + div animation

Question

Since I dont have either of these devices handy to test, which method would be faster on an iphone/ipad?

One large canvas (overlayed over a bg of the same size), that is cleared, and has new pixel data drawn to it each frame, at a certain position

or

A small canvas that updates each frame, contained in a div that is animated across a background

Answer 1

As it turns out iphone/ipad aren't even capable of running this small animation either way. I will have to look at alternative solutions for mobile/tablet devices.