A new study from the Pew Internet & American Life project reveals that a third of all American adults—35 percent—now own and use a smart phone such as an Apple iPhone.

The Pew findings come from a May 2011 nationwide telephone survey of 2,227 adults. From those interviews, Pew estimated that 83 percent of American adults own a cell phone, and that 42 percent of those cell phones are smart phones. Pew researchers then extrapolated that smart phones have penetrated into a third of the nation's population.

That's quite a jump, considering it was just 10 years ago that smart phones first made their way into U.S. consumers' hands. To put it into perspective, that means more American adults own smart phones than:

• E-book readers and tablets. A similar Pew survey (also in May) on e-readers found American ownership of the devices at just 12 percent. The good news for e-book readers: Growth is expected to double. Tablet computers, at just 8 percent, will have a much slower growth curve, say Pew researchers.
• Motorcycles. According to the most current data from the Department of Transportation, there were 7,883,446 motorcycles registered in the U.S. in 2009. If you figure the U.S. population in 2009 was roughly 305,530,000, less than 3 percent of Americans owned a two-wheeler. Still, motorcycle and scooter sales are rising along with gas prices.
• Passports. The U.S. Department of State reports it issued 13,883,129 U.S. passports last year. The U.S. resident population grew from 2009, hitting just under 308,746,000 last April, according to the U.S. Census Bureau.

Smartphone Adoption and Usage [Pew Internet & American Life Project]
35% of adults found to have smart phones [SF Gate]