Rating: 

Each section includes a reasonably complex sample that puts that section's material to use. Most of the sections also include a "Further Study" area that gives you some homework. This is where the user can expand his knowledge through research and working with the tools.

The book jumps around a bit by first going over simple UI patterns, then spending time talking about audio services and networking, only to come back and spend more time with UI controls, only to jump back into audio/video. Still, one has to remember that this is a reference book and not a novel so jumping around is ok.

The sample applications that I have tried so far are ok and I feel like I have a much better grasp on how the iPhone system works.

This book is not an XCode or Interface Builder tutorial.