A calculator example app for playing with Test Driven Development
There is documentation in the code so you can understand what is going on. Also the appldocs are available here. You should check them out if the code is confusing to you!
Missing Features To Implement/Test
The Division and Subtraction features are currently missing on purpose. We will cover these in an upcoming New York iOS Developer Meetup.
Feel free to start playing with the code before the meetup though!