Competition Rises for AT&T, as Does 3rd-Quarter Profit SAN FRANCISCO - T-Mobile USA, the underdog among the four big American phone carriers, has made aggressive moves to shake up the wireless industry this year - and AT&T in particular. But AT&T's results have not budged. AT&T, the second-largest American carrier after Verizon Wireless, reported profit of $3.8 billion in the third quarter, up from $3.6 billion in the same quarter a year ago. AT&T said that it added 363,000 contract subscribers - the most valuable type of customer - in the quarter, about double what it added last year. Also, subscribers left AT&T at a slower rate than they had before. Churn, the rate at which subscribers leave, was 1.07 percent, versus 1.08 percent in the same quarter a year ago. "We're setting the standard for 4G LTE speeds and network reliability," Randall L. Stephenson, AT&T's chairman and chief executive, said in a statement. He added that the expansion of the company's cable TV and phone service, U-verse, helped drive growth. Last quarter, T-Mobile reported growth of 685,000 contract subscribers - far more than other carriers. T-Mobile has said it wants to steal customers from AT&T by offering more customer-friendly options, like unlimited data and cheaper international roaming. But AT&T's latest results raise a question: If AT&T's customers are not leaving for T-Mobile, then who is? Chetan Sharma, an independent telecommunications analyst who does consulting for carriers, said that question could be answered only when the other carriers report earnings. T-Mobile will report its third-quarter earnings in early November, and Sprint will report earnings Oct. 30. "Whether or not they will have a lasting impact remains to be seen," Mr. Sharma said of T-Mobile's efforts. AT&T also said it sold 6.7 million smartphones, a record for the third quarter. It added 655,000 subscribers to its high-speed Internet service and 265,000 to its cable TV offering. Revenue climbed 2.2 percent to $32.2 billion. The revenue and net income, at 66 cents a share, slightly beat the expectations of Wall Street analysts. They had expected earnings of 65 cents a share and revenue of $32.2 billion, according to a survey by Thomson Reuters.