I’m looking to make an Android app that changes the look of the UI based on the device it’s shown on (4 inch phone, 7inch tablet and 10inch tablet). I know you have the fragments API and it’s probably that which I should use for this, but all the examples I’ve seen just have 2 activities sitting side by side and the code is a bit OTT for my needs (they have events passing between them etc).
Here is the comparison between a 4 inch device and a 7 inch device and how the different UI elements should move around (also note that element A can change design between the two devices).
Any ideas on how I would go about doing this, or if anyone has any sample code that would be fantastic!

I think you should probably design different xml for each size. You can use the qualifier in the layout dir for different screen size. http://developer.android.com/guide/topics/resources/providing-resources.html#AliasResources