A Guide to the iOS 7 Status Bar

In previous versions of iOS, the status bar was untouchable other than color adjustments. iOS 7 makes the status bar transparent, and, if your view doesn’t make use of a UINavigationController, then the 20 points of space at the top of the screen that the status bar sits on top of becomes usable space. This change makes the UINavigationController a major factor in the development of your app.

Read the full tutorial here