"Pre-orders do work on iPhone"
Still in the process of reading, but so far it is everything I had hoped it would be. In the mean time, I wanted to post for others who had pre-ordered on iPhone and had trouble downloading. It is possible without any major trouble, don't fret! Simply go to "Settings" (next to stats, on the right at the bottom) and click "Refresh Complete Library". I can't promise it will work for you, but it did for me. I hope this helps, and enjoy.