PerfectReader!

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.

Foxit Reader is a free and light-weight multi-platform PDF document viewer. Its core function is compatible with PDF Standard 1.7.

Evince is a document viewer for multiple document formats. It currently supports pdf, postscript, djvu, tiff, dvi, cbr, cbz, etc.

FBReader is an e-book reader for various platforms.

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. You can buy ebooks for reading on your computer, Apple device, Android device, Nook, or Sony eReader in the Google ebookstore. All purchased eBooks are backed up online, and your page positions are automatically synced between devices.

It is an all-in-one solution to read and manage your eComic library. You can think of it as ITunes for eComics with much of the same functionality.

Innovative book reader with powerful controls & full functions:

Aldiko is an e-book reader application for the Android operating system. It supports the EPUB industry standard format for digital publications and incorporates facilities for browsing online catalogs on thousands of books (including thousands of free public domain work) and downloading them directly into the users personal library. The application features a bookshelf-like user interface that lets user navigate their collection of eBooks. It also provides a customizable reading experience through configurable font and background color, font size and type, margin size, display brightness, page turn mode, etc. Additionally, the application allows users to import their own books to read them on the go. »

EPUBReader is a Firefox addon which lets you read ePub-files just in the browser. You don't need to install additional software!

A fork of the last GPL version of EBookDroid. Supports the following formats:

With GoodReader on your iPhone, iPod Touch or iPad, you can read virtually anything, anywhere. Books, movies, maps, pictures; GoodReader puts it all in a single app, right in your pocket.