It's useful for "1" track digital albums (where the album is one big file without chapters/bookmarks), Podcasts (especially in the .mp3 format), and singular songs (there are parts of a song that you just want to hear without having to manually rewind or fast forward to get to that part(s)). It would be great if not only A-B repeat could be built-in - BUT ALSO the ability to bookmark the selection and store them (there's already an app that does this - BUT THAT APP is no where near the capability & functionality of Poweramp (though I don't think it's intended to be anyway).