Whatever app is playing, the cover sits on one side of the camera and the song's wave on the other. Open it for the full player.

Built into Ledge for macOS.
Swipe sideways with two fingers on the notch or a player: left plays the next song, right goes back.
Progress, volume, timed lyrics and your speakers, a click away.
The pill steps aside while a video, game or other app fills the screen.