Audible - Audible is the world’s largest provider of premium audiobooks and spoken word content.
Universal Book Reader - Just like its name, Universal Book Reader is really a universal book reading application allowing you to read the eBooks from the convenience of your smartphones.
LibriVox - free public domain audiobooks
Cool Reader - Fast and small cross-platform eBook reader for desktops and handheld devices
DigitalBook.io - Free audio books and eBooks. Search, browse, listen, read and download over 100,000 free audio books and eBooks.
iReader - iReader is one of the most accomplished ways to read the books right from your smartphones.