Learn Objective-C on the Mac
Also on APress, this is _the_ book for learning and mastering Objective-C. Great writing, very easy to understand, and excellent as both a tutorial and reference. The authors assume you already know a little C syntax (from C, C++, Java, etc), so this is the key text for switchers. Still not figured out memory management retain counts and auto-release pools? Protocols, categories and inheritance a mystery? It’s all in this book. Recommended for all iPhone developers.