Kobo Audiobooks - Experience the joy of being told a story
Audiobook Builder - Audiobook Builder is a software that enables users to turn their audio files into audiobooks which they can sue then on their iPhone, iPad, or any other Apple devices.
Scribd Audiobooks - Unlimited access to 30,000 audiobooks
AudioBookBinder - Got a lot of audiobooks in MP3 format and would like to listen them on your iPod?
Prologue - Audiobook player on iOS for Audiobooks hosted on a Plex media server
Listen to books for free - Listen to books for free is an app by Anyreads that allows users to listen to up to 7000 audiobooks right on their mobile phones.