AT&T said its second-quarter earnings fell 10 percent after a year-earlier gain, but the telecom company added more long-term wireless subscribers than expected, thanks to a jump in smartphone users, including consistent growth in Apple Inc. iPhone owners.

Dallas-based AT&T has experienced slowing growth in contract subscribers, reflecting concerns that the explosive growth in the industry’s most lucrative part of the business had largely dissipated. Yesterday, AT&T said it added 331,000 contract customers, more than Wall Street was expecting.

Meanwhile, AT&T executives also discussed the pending acquisition of T-Mobile USA from Deutsche Telekom AG.