I am currently going through the React-Native tutorials. I began with the Getting Started tutorial, where I made a new react native project and successfully managed to run the project on my device.
I then started the Props tutorial, I copied the code snippet and tried to run the project again and had the following error message show up on my screen:
I guess it is an error caused by not matching name of project and your registered component.
You have inited project with one name, i.e.
react-native init AwesomeApp
But in your index.ios.js file you register other component
AppRegistry.registerComponent('Bananas', () => Bananas);
When it must be
AppRegistry.registerComponent('AwesomeApp', () => Bananas);
If your component name does match, ensure you don't have any other react-native/node process running in another terminal.