Another app for readers - Calibre

calibre is an e-book library manager. It can view, convert and catalog e-books in most of the major e-book formats. It can also talk to a few e-book reader devices. It can go out to the internet and fetch metadata for your books. It can download newspapers and convert them into e-books for convenient reading. It is cross platform, running on Linux, Windows and OS X.

Calibre's Manual