Even with the release of iPhone OS 3.1.3, you are not allowed customize the look & feel of the iPhone background and icons. The only thing that Apple lets you change is the wallpaper of the lock screen.
That’s not enough.
I know quite a number of iPhone users are convinced to jailbreak their iPhone because of this single application: Winterboard. Winterboard is one of the most popular applications in Cydia that lets you completely change the look & feel of your iPhone including background, icons, keyboard, sound, SMS background, etc. It’s just fun and makes your iPhone stand out from the crowd.
A couple days ago, Jay Freeman, the creator of cydia, has put up an updated version of Winterboard (i.e. 0.9.3154-1) with a number of bug fixes and some exciting enhancements. It has been a long time since Winterboard get updated.
The new version comes with a new configuration screen and it can be accessible via Settings. Here are the details for the update: