I like discovering new music and I often do so by listening to random Playlists.
Sometimes those Playlist are dozens of hours long. I want to go through all the songs only once in order to mark my favourites. Unfortunately, I often do not have the time to go through them all before I want to change music style or stop listening music.
It would be fun if I had a way to mark which song of a particular playlist I was listening to last, so I can start listening where I was. Or some type of playlist that removes a song once it was played once.