If you ever wanted to have joint control over listing sessions with friends or family, Spotify is introducing a feature that enables exactly that. It's called Group Sessions and is being made available in the beta version of the app for testing right now. The company has been working on the functionality for quite some time but the timing of this wider availability couldn't be better since it gives us something to mess around with while in lockdown
According to Spotify's support page, you can start a session by tapping the same connect button that you'd use to cast your music and scrolling down to where it says "Start a group session." Get your friend to do the same and then one of you can scan the other's code to join forces. Your unique music waveform works as Spotify's take on a QR code.
Now you share the same play queue and can both add, remove, reorder, or skip tracks at will. I've only been able to test it with two accounts, but it apparently supports more than that (good for when we're eventually allowed to have parties again). You can also cast music to a speaker or smart display as you would normally. To leave the session, head back to the same spot and tap the button to stop sharing.
As Droid Life points out, this is basically what the Nexus Q did way back in 2012 — I'm sure it's going to more successful this time around, though. Of course, it's long been possible to create collaborative playlists in Spotify, but this takes things to the next level by allowing real-time co-control. It sounds like the feature will evolve over time, too, so maybe we'll end up being able to share codes with friends further afield so we can have listening parties from different places without using a third-party like Zoom.