MobileDevChallenge
The code was built on Mac Mini (mid-2011), Mac OS 10.8.5, Xcode 5.1.1, SDK 7.1 and tested only on a simulator. Within shown environment the build results in 0 errors, 0 warnings, 0 static analyzer issues, 0 leaks.
Video of how this code runs: https://youtu.be/q2QhWcwpLYk