Anyone know how the people on ebay such as "mobilehotshots" can unlock your phone? (With no hardware, changes no simcard, entirely over the net.)
Here's an example listing: http://www.ebay.com/itm/Factory-Unlock-Code-Service-for-AT-T-USA-Apple-iPhone-3-3G-3GS-4G-4S-Permanent-/221116379439?pt=LH_DefaultDomain_0&hash=item337b90312f (There's lots of other sellers on eBay you can search for, I have no affiliation with any of them. Don't take this link as an endorsement.)
They claim that you send the your IMEI number and they email you back when they've unlocked it. Then you (in the iPhone's case) restore from a backup and your phone is unlocked when activating again.
Sounds like a scam.
But-- the thing is they have like 38,000+ feedback rating , with almost 5,000 this month and only 5 negative ratings. Anyone know how they do this? Is it some guy who works at AT&T unlocking your phone against the rules? Is there some telecom standard they're exploiting? Is it some formula where your phone has a key and at&T has a private key and they've figured out how to reverse it? Can the phone be re-locked at a later date?
Anyone know how this works exactly? Looking to unlock my in-contract iPhone 4s.





