This is just a note to anyone who might be considering this book. I find it very well-written and easy to follow without being too simplistic. The examples are fun to put together and thought out very well. There are books on Objective-C that go into more depth in terms of software design and patterns, but this book give excellent coverage to the IOS platform. I've struggled with several of the examples mostly because I want to add my own customizations to expand my knowledge. I've stuck with the book and working through it has been fun and challenging.
A minor editorial criticism I have is that in a few places in the book, the text notes that certain code segments appear in bold, such altered code or things to take note of, but there are some places where the bold type is missing.
A major point of praise I have for the book is that it's encouraged me to write large sections of my own code as well as given me what I need to know to accomplish that. That's actually sped up both the learning and development process for me. Comments are encouraged.