Calibre is pretty good imho. Nothing compares to organize ebooks, remove drm so that I can read kindle ebooks on kobo, and convert files to kepub so I still get

Calibre is pretty good imho. Nothing compares to organize ebooks, remove drm so that I can read kindle ebooks on kobo, and convert files to kepub so I still get the kobo specific enhancements on non-native kobo epubs.