Been reading a lot into UI design lately and Fitts Law keeps popping up.

Now from what i gather its basically the larger an item is, and the closer it is to your cursor, the easier it is to click on.

So what about touch screen devices where the input comes from multiple touches or just single touches.

What are the fundamentals to take into account considering this?

Should it be something like, the hands of the user are on the sides of the device so the buttons should be close to the left and right hand sides of the device?

Thanks