I phone unlocked

AT&T is paying millions to be the exclusive United States provider of Apple’s much-hyped and glowingly reviewed gadget, the iPhone. It took 17-year-old George Hotz two months of work to undermine AT&T’s investment. Mr. Hotz, a resident of Glen Rock, N.J., published detailed instructions online this week that he says will let iPhone owners abandon AT&T’s service and use their phones on some competing cellular networks. Two weeks ago, a company called Bladox, based in the Czech Republic, began selling an $80 device called a Turbo SIM. The thumbnail-size card, attached to another carrier’s SIM card and inserted into an iPhone, tricks the iPhone into thinking it is running on the AT&T network even when it is not.