SwiftBites - Learn how to code in swift with interactive mini lessons
calibre - Ebook manager, viewer & converter
Flowlingo - Get fluent in a language through content immersion
FBReader - FBReader is an e-book reader for various platforms. Features:
Google Play Books - Google Play Books lets you search, preview, and buy millions of books using Google Book Search.
udemy-dl - Download courses from Udemy for personal offline use