How to use custom fonts in Storyboard for iOS 7 and 8 at the same time?

So far I have been working on an iOS7 project with Xcode 5 and have included fonts via runtime attributes ( Custom font in storyboard? )

I had to download iOS8> Xcode 6 the other day, and the current method of importing fonts and using them in a storyboard is to just drag the font into the project and set it as a custom font ( How do I make custom fonts during development in Xcode 6? )

The problem is that the second method does not currently work with an iOS7 device, and if I add the fontName attribute for the runtime, it works with iOS7 but stops working with iOS8.

Any solution to work with iOS7 / iOS8 at the same time?