This book provides a serious, in-depth look at Apples External Accessory framework and the iPhone Accessories API. Youll learn how to create new, integrated solutions that combine iPhone apps with dedicated hardware. The iPhone OS Accessories API expands the opportunities for innovative iPhone developers, allowing you to control and monitor external devices, whether youve built them yourself or obtained them from a third party. What youll learn Develop accessories and apps for the iPhone and iPod touch. Use Apples External Accessory framework to create hardware/software interaction. Control and monitor external devices using the iPhone Accessories API. Use the specific controller classes within the iPhone OS software development kit. Build and control your own accessory. Get your accessories approved by Apples AE program. Who this book is forThis book is for iPhone and iPod touch developers who want to write apps to control external accessories and hardware developers who want to create accessories for iPhone and iPod touch. This includes embedded systems programmers who have been left out of the iPhone gold rush until now. The iPhone OS Accessories API expands the market of iPhone developers yet again, and this book is for all those developers wanting to use these new APIs to control and monitor external devicewhether self-built or acquired from other sources. Table of Contents Accessory Overview EAAccessory Framework EA Framework Design Patterns The Game Controller Specifying a Pong Game Coding a Pong Game Adding the Game Controller Improving the Design Apple Developer Programs Hardware Design Firmware Everything Else