I am writing a android app that will pull in a list of all the users friends so they can tag them in the photo but displaying a large box of the friends with their photo ins
If you watch the network traffic from Facebook's iPhone app, you can see they make this FQL call to get the users top 10 friends they communicate most with:
SELECT uid2, communication_rank
FROM friend where uid1 = me()
ORDER BY communication_rank DESC LIMIT 10
Unfortunately this is not available to applications by default. You would need to contact a Facebook engineer to get this field enabled for your application.