Uses the Spotify API to find songs, then allows them to be added to a queue (using SQLite3) which will be added to the top of the native Sonos queue.
This means I can choose a main playlist to be played on the Sonos and have people add songs on this app which will then play in the order they were added but still keep the main playlist playing when this queue runs out. That's how my friends and I prefer it to work.