calibre - Ebook manager, viewer & converter

CBconvert - A comic book converter with support for .cb*, .pdf, .xps, .epub, .mobi and directories.

Google Play Books - Google Play Books lets you search, preview, and buy millions of books using Google Book Search.

TEBookConverter - Portable software for cloud, local, and portable USB drives

ReadOut - ReadOut is a text to speech conversion app by Flying Phoenix that offers features to enable you to import text from a variety of different sources to convert it into speech in various languages right on your mobile phone.

Convertio - File Conversion in the Cloud