1) I was underqualified for the position that I applied for. So they offered the internship.
2) Since I did not have a lot of (work) experience I guess it was a gamble for them to employ me "just like that". So it could be seen also as an qualifications test maybe.
3) Visas are hard(ish) so not employing me made it, let's just say more legal. Paperworkswise I've been working as a freelancer for their branch in a different country.
(By the way: the Khan Academy iPad app actually shipped _today_. Congrats to everyone back at Khan HQ!)
If you're an iOS dev who wants to be mentored for a few months by a former UIKit author, hit me up. :) andy@khanacademy.org
Sounds like a stellar internship!