dyld: Library not loaded: @rpath/libswiftCore.dylib

Question

I am trying to run a Swift app on my iPhone 4s. It works fine on the simulator, and my friend can successfully run it on his iPhone 4s. I have iOS 8 and the official release

Answer 1

The most easy and easy to ignored way : clean and rebuild.

This solved the issue after tried the answers above and did not worked.