I loved this book. I really appreciate the way this book "peels the onion". Starts off with the simplest of apps, and with each successive example brings in all the necessary information on the Apple dev tools, iPhone SDK, Objective C language, and the Cocoa frameworks. Key concepts are adequately explained and unfold gradually.
If you have a C/C++/Java/Python or similar background (who doesn't these days), this book will provide you with all the skills you need to develop great apps. It is not necessary to first learn Objective C before diving into this book. Reading this book is much more efficient than reading the detailed developer documentation distributed by Apple.
After reading this book, I feel completely comfortable tackling any of the APIs and have a thorough understanding of key concepts.
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