The current version of the app across all platforms allows users to sort their library by recent play, recent addition, alphabetical order, creator, or custom order.
Allowing users to sort their library by runtime would be useful to many, as I know many people (myself included) look for collections of songs—whether albums or playlists—that last the same amount of time as an activity they may be performing (e.g. washing dishes, working out, taking a nap). It would be nice to be able to look at albums or playlists in the same range of runtime when selecting music to put on for a certain activity. For a playlist folder, maybe an average runtime of the included playlists could be used to determine its position.
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