I've been working on a pacman clone in HTML5 for quite a while. (http://pacman.platzh1rsch.ch)
One important thing for me was always to keep it responsive, so it would be playable on all different handheld sizes. The big problem wit that is: it is way to hard to play on a mobile device.
On a desktop or laptop you can control Pacman using your keyboard's arrow keys or W-A-S-D, which - in my opinion - is really easy.
For touchscreen devices I added some buttons into the game and also the support for swipe gestures. Anyway, turns out it's still way too difficult to play for most of the users.
Do you know any better options on how to solve this issue?
EDIT: Just adjusted the game to detect swipe gestures on the whole screen and I think it is already a pretty nice improvement. Thanks for all the hints, and suggestions!