One thing that I think could really make Spotify better is a way to add notes or a user description of sorts to songs once they're added to a playlist. For example, I created a playlist called Trailer Tracks that has a number of songs featured in popular movie trailers. However, there is no way for me to tag each song with the trailer it was featured in.
A way of doing this, or allowing the admin of the playlist to add a description of why a certain song was added or what it means to them could really add a new twist on Spotify and take music sharing to a whole new level.
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