iOS 4 in Action, the update to iPhone and iPad in Action, covers up to version 4.2 of the SDK, which allows you to develop applications for both the iPhone and the iPad devices. Beyond covering the basics of iOS development, this edition also explores exciting topics such as multitasking, the game center, AirPrint, and iAd. The reader is provided with step-by-step instructions on how to integrate the APIs into new or existing applications.
This book guides you from setting up dev tools like Xcode and Interface Builder, through coding your first app, all the way to selling in the App Store. There are many sample applications to work from including a chat client, video game, interactive map, background audio, and many others.