Apple's iPhone has reached unprecedented sales levels in recent years, with more than 110 milion units sold worldwide. The demand is not expected to subside any time soon, particularly in the United States, as a survey has found that 35 percent of American consumers want to buy the forthcoming Apple iPhone 5.

The survey by Pricegrabber reveals that more than one out of every three U.S. consumers wants Apple's new iPhone 5 when it is released.

Even if they recently got an iPhone 4, the survey shows they still want the iPhone 5. Demand for Apple's smart phone, run by the company's iOS operating system, is unprecedented.

"Our survey data confirms the strong following Apple has built around its iPhone, with more than one-third of consumers planning to updgrade to the latest model only a little over year following the release of the iPhone 4," said Pricegrabber general manager Graham Jones, in a statement.

Pricegrabber's survey was conducted among 2,852 online consumers.

Google's Android is the most popular smart phone operating system, but there are many phones that use it. Thus, Apple's iPhone is easily the world's bestselling smartphone.

Apple first released the iPhone in 2007.