Iphone as purely offline device (Rhapsody)

[ajzig5]

I currently use Rhapsody to transfer tracks to my mp3 player.  These are tracks I have not purchased and are not local.  I must update the license on them every so often.  I have the ability to temporarily download them to my mp3 player.  Is it possible to use an iphone with Spotify Premium in a similar way?  In other words, can I use an iphone as a purely offline device with Spotify Premium?  Do unpurchased tracks have to be streamed or can I actually temporarily download them to my device?  Thanks!