calibre - Ebook manager, viewer & converter
SwiftBites - Learn how to code in swift with interactive mini lessons
FBReader - FBReader is an e-book reader for various platforms. Features:
Flowlingo - Get fluent in a language through content immersion
Google Play Books - Google Play Books lets you search, preview, and buy millions of books using Google Book Search.
Cool Reader - Fast and small cross-platform eBook reader for desktops and handheld devices