This is a possible solution to the Matchismo assignment for the Stanford CS193P IOS programming course. This solution is slightly different from what's done in the course in that it uses a card-back graphic. It also corrects an error that exists in the sample code given during the class with regard to a possibly array index out of bounds issue. It is also slightly different in that I prefer to instantiate my iVars explicitly in some cases, like the game model, rather than lazily. If, for some reason, your instantiation fails, it's a pain to track down the fact that your entire array is nil because it was never created because you never actually called the getter.