iphone restarts when I try to run my app

Hey I can't put any code into here because there is too much. but when I put my game onto my phone it crashes the phone and it restarts itself.
I have an iPhone 4 running 7.1.2 Xcode 6.

I'm using sprite kit with objective c. could there be anything that I have used that is only meant for iOS 8. I don't have a crash report as I don't have the developer licence.