Does this fall within Apple's policy of fair use? Would be great if there were an officially supported (paid) API for this, the technology and potential use cases are great. I'm afraid hooking something like this up to my Apple ID will get me banned somehow.
You are using other users' (mobile) bandwidth to do the transmission, and apples server resources to brute force/ddos request the data on the other side. I can't see them condoning this at all and simple not responding negatively to it could encourage this misuse. I would expect that kind of response from Apple.