There is no default value - it remains until your program is loaded and returned from application:didFinishLaunchingWithOptions:
If you want to save the image under program control, you need to place it on the screen manually, as the first thing that the program displays, and then release it through regular channels. It would be relatively easy on the iPhone to 5 (just put a large UIImageView with Default.png ), but, like the iPhone 5 and iPad, you have to make some decisions regarding which is displayed by default.
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