Some findings from playing with launch arguments:

Some of you might know you can override NSUserDefaults with launch args

This doesn't just apply to the standardUserDefaults, it also applies to shared defaults in App Groups

But what about the following scenario? Would you expect an int or a string?

By default, Foundation will translate launch args to a string. You can specify types with __blank__(forKey:) APIs for simple types, but you can also specify the type in the launch arg itself

Dictionaries/Arrays a fair game, just think plist xml styling