As time has gone on, Folders have become the most important feature of my desktop version of Spotify.   I hope to see the same functionality duplicated for the Android (and elsewhere).

For all tracks in Folders on the Android, please add, in order of value to me:
* Sort by Artist
* Sort by Album (in track order per album - very important for Classical music, especially).  
* "Unsorted", as found in the playlist sort option, is misnamed.  It should be called "Sort by Time added" and would also be valuable in the Folders.

Slightly off-topic: Inconsistency in the interface on various platforms makes Spotify a very, very uneven experience for me.  The Web Player is not useable for anything except new music discovery because its lack of folder support makes my playlists impossible to find.  The Roku version has no "play all tracks" option.  And the Android's sorting options are incomplete (but the new Filter is BRILLIANT, and works around many of my disappointments - thank you for that).    
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Joe, I have voted up  this suggestion, and hope others do so, too.
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Mark

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