How to develop a good touch GUI?

I've always developed appli开发者_高级运维cation for personal use on command line. Now I have to develop an app for android for a broad audience.

If I start now I would make and awful GUI. I need first to educate myself on the matter of building clear, efficient and usable GUI on a touch interface.

Any advice?

You could read the Android User Interface Guidelines and the iPhone Human Interface Guidelines

First thing first, don't think about how to build a good GUI. Getting yourself to know what is a good GUI is far more important. Try using different application to see which one you feel good about it. Then read the guide in the answer above.