Found in 1 comment on Hacker News
GoofyGewber · 2012-04-21 · Original thread
Depends on how you learn, I think the videos are very informative. They're not going to teach you everything, so buying a book or two would help a lot.

http://www.amazon.com/Beginning-iPhone-Development-Exploring...

The book is kind of dated, so I would recommend looking for something more recent.

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