According to a new survey among iPhone buyers in the United States, 73 percent prefer the high-end iPhone 4S, while 38 percent of those opting for Apple's smartphone reported switching to the iPhone from Android or BlackBerry.

The survey was conducted in April, by Consumer Intelligence Research Partners. The latest data found that the number of people switching from Android and BlackBerry smartphones to Apple's iPhone has seen a significant increase from 29 percent in the previous survey conducted in February to 38 percent in April. The survey was conducted on 7,348 subjects, 521 of which qualified to respond.

The number of consumers shifting to the iPhone, as per the latest survey, is even bigger than it was right after Apple released the iPhone 4S in the holiday season last year, when 36 percent of iPhone buyers were coming from another smartphone platform.

When it comes to capacity, the latest study found that Apple's 16GB version of iPhone 4S was the most popular among consumers. The latest data shows 50 percent of iPhone buyers polled in April chose the smallest capacity version, i.e. the 16GB iPhone. Meanwhile, 34 percent opted for the 32GB model, and the remaining 16 percent chose the high-end 64GB iPhone 4S.

Nearly three-quarters of all iPhone buyers in the United States went for the latest-generation iPhone, the 4S, while another 22 percent opted for the previous-generation iPhone 4. Apple's fourth-generation smartphone is available for purchase with a $99 price tag with a two-year service contract. The third-generation iPhone 3GS, which is free on contract, accounted for just five percent of the iPhone sales in the U.S.

According to the new survey, customers have increasingly opted for the high-end iPhone 4S over cheaper alternatives. The number of iPhone buyers in the U.S. who went for Apple's current-generation smartphone increased from 69 percent in the latest survey to 73 percent in April.

The study also shows a slight shift in carrier shares between February and April, as AT&T dropped from 53 percent of new iPhone activations to 51 percent, and Sprint slid from 13 percent to 12 percent. AT&T and Sprint ceded ground in Verizon's favor, and the nation's largest carrier saw its share increase from 34 percent to 37 percent of iPhone activations in April.