A free program for Android, by kryptow.

The PDF to EPUB – E-Book Converter app can convert almost any document file to a digital book file in EPUB format. The app allows you to convert to various other formats such as docx, epub, html, htmlz, lita, lrf, mobi, odt, pdf, png, and others.

Conversion is done on the device and the app can also send the files to the cloud if you wish. This is especially useful if your device has a weak internet connection. In this case, the app will send the file to the cloud and you will be able to continue using the device and not have to wait for a connection.