Aux Battles
Aux Battles runs in the browser at auxbattles.app, so there's nothing to download here. Create a room, share the 4-letter code with friends, and everyone answers a music prompt with a song from Spotify, YouTube, or SoundCloud. Vote blind, see who wins the round, climb the leaderboard. Free, no account.
The blind voting mechanic is a nice touch — it makes the game about the song choice rather than who submitted it. The no-account, room-code flow also keeps the barrier to playing with friends low.