Apple released its rulebook for what can and can’t exist in the iTunes App Store and, believe it or not, there are plenty of apps already in the store that break multiple rules. Here are just a few.
That’s the app. "Nothing." Guess what it does? Nothing. Guess which rule from Apple’s "App Store Review Guidelines" it breaks?
"Apps that are not very useful or do not provide any lasting entertainment value may be rejected."
The use of the word "may" might be the key there.
Whatever the case, nothing never hurt anybody (except that this Nothing costs money).