Calibre is a free and open source e-book library management application made by users, for users. Many languages, designed around the concept of the logical book, i.e., a single entry in your library that may correspond to actual e-book files in several formats.
Multi-platform, fast and packed with features, Okular allows you to read PDF documents, comics and EPub books, browse images, visualize Markdown documents, and much more.
Evince (or GNOME Document Viewer) is a document viewer for multiple document formats: PDF, Postscript, djvu, tiff, dvi, XPS, SyncTex support with gedit, comics books (cbr,cbz,cb7 and cbt) and others. See Supported Document Formats for details.
Amazon Kindle software lets you read ebooks on your Kindle, iPhone, iPad, PC, Mac, BlackBerry, and Android-based device. You can discover and read over 630,000 books in the Kindle Store, including the latest bestsellers and new releases.
Google Play Books lets you search, preview, and buy millions of books using Google Book Search. Books in the public domain and certain copyrighted books can be read and downloaded in their entirety for free.
Create, Convert, Review and Edit PDF Documents on Windows, macOS, and Linux.
Apple Books is the single destination for all the books you love, and the ones you’re about to. Browse the Book Store, join Oprah’s new Book Club, keep track of what you’ve read and want to read, and listen to enthralling audiobooks. All in one place.