This book is a guide to audio programming for the iOS platform, created by iZotope, Inc. The guide presents several methods for handling audio in iOS, and includes example code, drawn largely from the samples provided by Apple, for each step of the process. The guide also contains pertinent information regarding digital audio and signal processing, specifically as it relates to iOS development. 

A pdf version of this guide, as well as the iOS SDKs mentioned within, can be found at www.izotope.com/ios