GUI Tutorial or free GUI Manager like EZ GUI and NGUI for Android and iOS

What do you think is the best way to develop a GUI for mobile devices?
Especially with Android, it’s so many different resolutions. I would like that the GUI looks the same on each devices.
Is there free plugins or good scripting tutorials? Or it’s just really good with NGUI or EZ GUI?
Unfortunately I have no experience with the two GUI Managers. Which is better for mobile GUI development?
Is there a way to differentiate ldpi, mdpi and hdpi devices like in Android SDK?

First of all, NGUI is worth every cent! btw if you’re makin mobile game you’ll get ya money back anyways… lol

Anyways this guy shows a good way of creating GUI for mobiles!