There’s a rumor going around that Apple and Nokia are going to partner and produce a mobile iTunes application for the Nokia N91. Nokia is denying it, but the phone’s still months away from its launch, so there’s plenty of time for things to change.

As I see it, there are sort of three levels of iTunes integration for portable devices:

  1. The device syncs with iTunes and can play encrypted iTunes Music Store .m4p files. Right now, this is pretty much just the iPod, although the long-rumored Motorola iTunes phone will join it once it’s released.
  2. The device syncs with iTunes and can play MP3s and maybe unencrypted AAC files. Before the iPod took off, most MP3 players fit into this category, but I don’t know if Apple has continued supporting their competition.
  3. The device and iTunes don’t know anything about each other, and the user is stuck looking for third-party tools.

I suspect that the N91 will fit into the second category–just plug it into your computer using a USB cable and iTunes will copy things over. It’s possible that we’ll need a bit of glue code, but that shouldn’t be too hard to write. Worst case, it should only take a few hours to write something that can read through iTune’s XML database and copy playlists to the N91.