Cool Reader - Fast and small cross-platform eBook reader for desktops and handheld devices
Goodreads - See what your friends are reading.
Gitden Reader - For those book readers who want a flow while reading their favorite books via their smartphones will surely like using this application because this simple book reading app has lot of reading features offer to them.
LibraryThing - A home for your books.
FBReader - FBReader is an e-book reader for various platforms. Features:
GoodBooks.io - Largest curated collection of 8,500+ book recommendations.