Written for Xcode 4, iOS 4 in Action guides you from setting up your development environment, through coding your first app, all the way to selling in the App Store. Work through sample applications including a chat client, a video game, an interactive map, background audio, and more as you explore the iOS 4 SDK. Version 4 of the iOS SDK adds powerful new features like multitasking, GCD, blocks, and iAds. With the release of Xcode 4, it's easier than ever to get programming, even if you're new to Objective-C. iOS 4 in Action, written for Xcode 4, is a detailed, hands-on guide that goes from setting up your development environment, through your first coding steps, all the way to creating a polished, commercial iOS 4 application. You'll run through examples from a variety of areas including a chat client, a video game, an interactive map, and background audio. You'll also learn how the new iOS 4 features apply to your existing iOS 3 based apps. This book will help you become a confident, well-rounded iOS 4 developer.