T-Mobile estimates there are more than 1 million unlocked iPhones on its network already. The underdog carrier says it can offer consumers a better deal on service, with unlimited data.

The company's focus is on the HSPA+ rollout now, but next year it plans to launch commercial LTE service. That new network, which will be built with the so-called LTE Advanced system in version 10 of the standard, will provide even faster performance than HSPA+, Ray said. He declined to predict its speed.

The IDG News Service