Spotify has the following intent-actions:
metadatachanged,
playbackstatechanged, and
queuechanged.
queuechanged contains no extra data.
playbackstatechanged has a boolean value for “playing”, and a value for playbackPosition.
metadatachanged contains artist, album, track, length, and id values.
You can get Artist, Track, and Album names when the track is changed (manually or automatically) by using com.spotify.mobile.android.metadatachanged
If Spotify is paused and started again, only playbackstatechanged is broadcast.