I could be wrong. But I don't see the requirement: http://makeappicon.com/ios7icon

And also Xcode doesn't complain:

![screen shot 2014-05-05 at 11 40 03 am](https://cloud.githubusercontent.com/assets/651899/2881565/b42d3f14-d484-11e3-9e81-3e074a32a630.png)