T-Mobile has used its third quarter conference call to admit that it expects to suffer subscriber churn due to the arrival of the iPhone 4S. As the only one of the nationís four carriers not to sell the iPhone 4S, it has lowered its outlook for the critical fourth quarter. The company said that although it had made net gains in subscribers over the third quarter, it expected to lose subscribers switching to carriers ìdue to competitor launches of the iPhone 4S.î
