Versus
Pick an artist and Versus pulls their whole catalog, every album plus the alternate versions. Then you battle: two songs, pick the one you'd rather hear, with 30-second previews when you need a refresher. Enough battles and you end up with a ranking across the entire discography.
Settle themed sets like Openers and Closers, see which songs moved versus your full ranking, and share the result as a card or a link your friends can rank against.
Coming to the App Store.