On the iPhone simulator everything works fine. When building the App for the iPhone i get the error:
A bundleURL is required to create an RCTRootView
In the AppDelegate.m i uncomment the following line;
jsCodeLocation = [[NSBundle mainBundle] URLForResource:@"main" withExtension:@"jsbundle"];
And downloaded the prebuild main.jsbundle to the iOS folder in the project root:
curl http://localhost:8081/index.ios.bundle -o main.jsbundle