I have a cool idea. I want to make 2 themes, one with a black and one with a white/grey look. I just want to take the ui of the app store for the black theme and the ui of the music app for the white one. All native apple apps (except passbook, weather..) should have this design. I want to change the navigation bar, the tab bar and the tabs and so on. The problem is: i dont have much skills in themeing apps. Can you help me to do this?