Mobile app analytics firm Localytics yesterday published a widely-cited report measuring the ratio of AT&T to Verizon iPhone 4s in the United States, finding that a surge over the past two months has increased Verizon's share to over 32% just four and a half months after the device launched on the carrier.
Summer has seen significant growth in Verizon's market share. After spending most of the spring at roughly the same share, Verizon has seen consecutive monthly jumps, grabbing 7% of the market for itself in May and June.
Why the recent uptick in Verizon adoption? One reason may be Verizon's unlimited data plan, which they are scheduled to do away with on July 7th. AT&T officially discontinued its unlimited data plan in mid-2010, although existing customers were allowed to keep their plan as long as they remained AT&T customers.
We do, however, have significant reservations about Localytics' data and how closely it correlates to actual device sales, based on what is known about iPhone activation numbers. Looking back at earnings releases from the two carriers, Verizon had announced 2.2 million iPhone activations as of the end of the March quarter, at which point in time Localytics data put Verizon's share of the U.S. market at 22.4%. In order for Verizon to have held that market share, AT&T would have had to have activated on the order of 7.6 million iPhone 4s by that time.
AT&T's iPhone 4 sales numbers are harder to gather due to a mix of iPhone 4 and iPhone 3GS sales, but total iPhone activations for the carrier appear to be in the range of 15 million since the launch of the iPhone 4 last June. It is true that AT&T's iPhone 4 sales are clearly somewhat lower than that given the inclusion of some new iPhone 3GS sales in that number and the fact that AT&T also counts used units that are resold or handed down and reactivated by new users, but we find it hard to believe that new iPhone 4 sales were only responsible for half of AT&T's total iPhone activations over the period.