David wants to know if he can listen to an audio book with his iPhone as well as his Android phone. Leo says he should, unless Apple does something different to them when buying them off iTunes. But if the audio book is from Apple's iBook Store, it's copy protected with the ePub format. He would need to strip it in order to play it on another platform. There are programs and plugins that do that, but they tend to be fly by night. TunesKit has one called iBook Copy for Mac. It has a free trial.