I literally tore my hair out while developing and attempting to market my iPhone app! There were so many things that I simply didn't realise I had to do - like guerilla marketing, creating elevator pitches, pre and post launch research, etc.
As I learned such a lot, I decided to document it all in the hope that other developers would benefit, and so I've just launched my first eBook called "How NOT To Write an App". As its name implies, the eBook takes the reader through the things that should, and shouldn't, be done when developing an app.
It's available on Amazon, Barnes & Noble, Apple's iBookstore, etc. and is aimed at all types of smartphone app developers (iPhone/Android,etc.) it's not a programming book, but rather aims to equip the developer with all the other tools needed to help his app become successful.