My 2009 Fit Sport has a USB port in the upper glovebox. I never really used it as intended, to play MP3s off a flash drive. I would just plug my phone into the aux port. I recently upgraded my iPhone to one that does not have a headphone jack and I didn't want to deal with an adapter or cable. So on a lark I tried this $13 USB bluetooth adapter:

Lo and behold, it works! I don't use the aux feature of the bluetooth adapter - I just leave it plugged into the USB port in the upper glovebox. It paired with my phone in a snap, and just like that, I now have bluetooth audio in my little old Fit!

It's not perfect by any means: as Amazon reviewers have noted, there's a few second delay when playing/pausing audio. I can't render an opinion on music quality because I only listen to podcasts and navigation while driving. The radio display doesn't show meaningful information, which doesn't matter to me because I keep my phone mounted on the dashboard.

All in all, it's well worth the tradeoff and solved a problem for me.