• by Mark Walsh  @markfwal, June 5, 2013

Last year, research firms reported that smartphone penetration had crossed the 50% mark among U.S. mobile users. The Pew Research Center’s Internet & American Life Project just issued a report which finds that a majority of Americans now own a smartphone of some kind.

For the first time since Pew began tracking smartphone adoption in 2011, more than half (56%) of cell phone owners surveyed in April and May said their phone is a smartphone, and 58% said their phone operates on a smartphone platform.

Taken together, 61% said “yes” to at least one of the above questions. With 91% of the U.S. adult population owning some type of cell phone, that means 56% of all American adults are smartphone owners. Over one-third (35%) have a feature phone, and 9% don’t own a cell phone at all.

In terms of demographics, Pew noted that smartphone ownership has been consistently high among younger adults -- especially people in their 20s and 30s -- and those with relatively high levels of household income and educational attainment. But smartphone growth has cut across every major population segment since last year.

Still, smartphone penetration has remained much lower among older Americans. Some 18% of those 65 and over now have a smartphone, for example, compared to 13% in February 2012. At the other end of the spectrum, eight out of 10 people between 18 and 34 have a smartphone.

Looking at smartphone platforms, Android owners now make up 28% of all cell owners, while iPhone is close behind with 25%. The share of cell owners that have a BlackBerry has fallen from 10% in May 2011 to 4% in the latest survey.

Among the more affluent users, the iPhone is the device of choice. Nearly half (49%) of those with household income of $150,000 or more have the Apple handset. By ethnic group, African-American mobile users are more likely than whites or Latinos to have an Android device than an iPhone.