Full source-code for the book "OpenCV for iOS" became available. Almost every chapter of the book describes a separate project. There are 15 Xcode projects for 17 chapters in the book. You can use these samples to learn how to use OpenCV for iOS even without the book. All projects were updated to support iOS 7 and Xcode 5.
You can find the code of the examples here: https://github.com/Itseez/opencv_for_ios_book_samples.