Calibre

Calibre is a free and open source ebook library management application developed by users of e-books for users of e-books. It has a cornucopia of features divided into the following main categories:


 * Library Management
 * E-book conversion
 * Syncing to e-book reader devices
 * Downloading news from the web and converting it into e-book form
 * Comprehensive e-book viewer
 * Content server for online access to your book collection

http://calibre-ebook.com

Latest Changes
http://calibre-ebook.com/whats-new

Updating
sudo python -c "import sys; py3 = sys.version_info[0] > 2; u = __import__('urllib.request' if py3 else 'urllib', fromlist=1); exec(u.urlopen('http://status.calibre-ebook.com/linux_installer').read); main(install_dir='/opt')"

Command Line Interface
http://manual.calibre-ebook.com/cli/cli-index.html

Fixing Broken Ebooks
epub-fix --epubcheck --unmanifested file.epub