Pressbooks - Create books: print and ebooks
calibre - Ebook manager, viewer & converter
Time Capsule - Transform your 2020 into a tiny, personalized book for free!
FBReader - FBReader is an e-book reader for various platforms. Features:
Papermine - Create stunning digital booklets.
Google Play Books - Google Play Books lets you search, preview, and buy millions of books using Google Book Search.