Thanks for the brilliant example. It really helps a lot with the problem of multiple screen sizes. I've been playing around with the formula you used, and trying to work out how I could get a sprite to position on the right hand side of the screen. But I'm still quite new to all of this and haven't had much success, any tips you could offer?
PS I had already tried anchoring my sprite (to the right side), but noticed a slight draw delay when loading on my Galaxy Tab 10.1. So you can see the white background behind sprite just before it's repositioned (which makes it look very unprofessional)