It takes a few minutes a week: pick a song, listen, vote. Voting is the part that matters — a round only works if people actually do it.
There is no sign-up. Every member arrives on an invite link from someone already playing, which works once and then stops — so if you were sent here without one, whoever sent it still owes you a link.
It is a private app for one group of friends rather than a service, which is why it asks for a display name and a password and nothing else. No email, no profile, nothing to delete later.