I have several ideas, but they all boil down to one common denominator: Make the mobile and desktop/web app features the same. They can look different, but they should all be there.
Examples:
-Add the queue function to the desktop app (AFTER you fix it on the mobile app: Link)
-Provide access to the artist bio and album reviews from the mobile app - this is a key feature that makes Pandora great and it's just missing from the mobile app.
Edit: Additional example:-Add the warning to the desktop app when you try to add a song to a playlist that already contains that song. /edit
Moderator Edit: Changing title for clarity