"Cannot load NSManagedObjectModel. nil is an illegal URL parameter"

I had the same problem but for me the modelURL was correctly set. The problem was that my *.xcdatamodeld file was not in the Copy bundle ressources anymore. I don't know why it disappear but to add it again fix the problem.

Here is how to fix it : You project > Build Phases > Copy Bundle ressources > "+" button and select you xcdatamodeld file

The problem is this line:

NSURL *modelURL = [[NSBundle mainBundle] URLForResource:@"FoodPin" withExtension:@"momd"];

modelURL is nil meaning that the system couldn't find the resource FoodPin.momd.

Make sure you have a Core Data model in your project named FoodPin. It will appear as FoodPin.xcdatamodeld in the Project Navigator.