When using YouTube app with Chromecast, All users connected to the same Wi-Fi network can connect to chromecast to queue songs and also control the playback.
It would be a nice feature to have on Spotify as well.
Currently, if more than one user connects to Spotify in Chromecast , the application is reloaded , droping the current user and removing the queued songs.
Edit: This idea has been reposted here.
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