I'm having difficulty understanding why apps are being letterboxed when simulating iOS 7 on the 5 and 5s. When using iOS 8 simulation it sizes properly. What could cause this? I don't have the 7.1 SDK on my computer, but I was told I didn't need it if using Swift (although I still get the problem on another computer when using the Xcode 7.1 SDK with Objective C and Xcode 6).
The picture below shows a default master detail application with zero lines of custom code written. The only thing that is changed is the development target (to iOS 7.1). I've checked the constraints on the views in the storyboard, and everything checks out.