Symfonium, DSub, Substreamer, Feishin and other Subsonic apps play your music from Usherr. Last.fm too, if you like.
In Broadcast: You, Your settings, Linked services, Phone apps. Administrators: Server, Watching, Apps on phones and TVs.
In Classic or Neu: Settings, Account & Access, Linked services.
Under You, Your settings (in Classic or Neu: Settings, Account & Access).
Switch on Let phone apps sign in, then press Make an app password. It’s the same app password reading apps use, never your sign-in password.
Add a Subsonic (or OpenSubsonic) server with the server address, user name and password the card shows. Away from home the phone needs Tailscale, as in Watch on your phone.
An administrator sets it up once under Set up Last.fm for this server, with an API key and shared secret from Last.fm. Then everyone can press Connect Last.fm; Send my plays to Last.fm and Love what I like are switches.
In Usherr’s player, a phone on mobile data can get smaller files: the streaming quality is set per device.