Verizon's iPhone sales doubled during its last financial quarter, with 4.2 million handsets sold. In its previous quarter, Verizon sold a mere 2 million handsets compared to 2.7 million sold at rival US carrier AT&T, according to Bloomberg.

Despite its lower iPhone numbers in the third quarter, overall Verizon apparently had more activations than AT&T due to Verizon's wide offerings of Android handsets. Verizon also narrowed the gap in iPhone activations during the third quarter compared to its second quarter; in Q2 Verizon activated only 2.3 million iPhones compared to AT&T's 3.6 million.

AT&T's fourth-quarter results won't come out until January 26, so we'll have to wait until then before we can compare Verizon's activations to theirs. Given strong sales of the iPhone 4S in the States, it's likely that AT&T has had a similar sales boost.