Some apps display a tutorial screen when the app is first launched after installation. To my mind there's few problems with this:
- I don't think people read these tutorials.
- Explaining the UI before the user has had any chance to take a look at it might be premature.
- Usually, if the UI needs explicit explanation it is too complex and should be redesigned. This is especially true with mobile applications which have different use context from desktop apps.
Pulse has already removed their tutorial screen in the latest version. Now they prompt for configuration options instead.
Winamp on the other hand has a hybrid approach where they provide configuration options and explain selected UI components.
Much better way for introducing advanced UI features to users is to point them out on the way. YouTube app does exactly this. At the first time user plays a video a simple overlay is displayed to point out that rotating the phone will change to fullscreen mode. Same happens first time user selects a tab.
Nichtlustig cartoon app tells user about advanced features in the app's info page. This way is much less intrusive than forcing a tutorial screen on user at the beginning.
If you find yourself thinking that the UI needs explanation or tutorial screen it might be worth considering redesign instead. Advanced features can be pointed out on the fly but key functionality should always be intuitive.
PS. Great Google I/O everyone! San Francisco here I come! :)