How to share code & xib files between iPhone apps?

Question

I'm in the process of creating an app. I'd like to have a pared down free version and a full paid version. Obviously, they will share a lot of code and some xib files. How to I share these without just duplicating them?

Answer 1

How about making it one project with some sort of key or switch or something like that which will distinguish with version of the code to run.

Answer 2

Create a second target (duplicate the main one) for the light version. You can then remove any files as necessary and define a preprocessor macro if necessary to distinguish between code for the lite vs paid version within a given code file.