Well, first look at the iPhone looks bad.

It appears that JavaScript function overhead is really high. Something around .7ms where on a desktop browser I would expect it at .001ms. This causes a general system slowdown that makes things very hard to work around. Will post more formal tests later, but you can see my current suite here if you're interested.

Check out this beta build (18 levels, not really balanced) of a our new game Pathos for the iPhone (completely free).