I have been working hard on a project on the Pico.
It currently shows the now playing track and album title and has a pause/play button and a skip track button.
I am going to keep expanding it.
You need Spotify Premium to use it.
Current issues:
You need to have a current playing track when booting up
If you leave a track paused too long you need to use something else (phone etc) to start the music again
