• by Mark Walsh  @markfwal, November 2, 2011

The surge in mobile app use goes well beyond “Angry Birds.” Nearly four in 10 (38%) adult U.S. cell phone owners downloaded an app in August, up from 22% in September 2009. Counting in phones that come with pre-loaded apps, half of us now have apps on our phones, according to a new survey by the Pew Research Center’s Internet & American Life Project.

Among the 10% of Americans who own tablet computers, the proportion of app-downloaders rises to 75%, reflecting the heightened appeal of apps on the devices’ larger screens. About a third (34%) use apps both on mobile phones and tablets. But the study notes that having apps and using them are not the same thing.

Among those with apps on their phones, roughly half (51%) use a handful of apps at least once a week, while 17% report using no apps on a regular basis.  Almost a third (31%) are app “power users” -- meaning that they use six or more apps weekly. When it comes to tablet users, 39% report using six or more apps on a weekly basis, while just 8% report using no apps regularly on the device.

In terms of content, the survey asked whether users had ever downloaded nine different types of apps. The most popular were those that provide regular updates about everyday topics such as news, weather, sports, or stocks (74%). That category was followed by apps that help people communicate with friends and family (67%) and ones that help people learn about subjects of interest (64%).

The Pew report noted that games continue to be the most popular apps in terms of use in the last 30 days, according to Nielsen’s quarterly mobile survey. The research firm also found that downloaders were more willing to pay for game apps than any other category.

The willingness to pay for apps has not changed much in the last year or so. The Pew study revealed overall that about half (46%) of downloaders had paid for an app at some point -- about the same proportion as the 47% who said the same in a May 2010 survey.

The profile of those most likely to pay for apps are affluent, college-educated men age 30 and older, living in cities. The demographics of app downloaders more broadly is similar, and remains much the same since 2009. However, the gap between men and women has since decreased.

Despite the rapidly growing uptake of apps, the Pew report concluded that downloading and use are still fairly low, given the range of activities that people engage in on their phones.

"It's too early to know whether by providing instant, direct connections to information, apps are a game changer,” said study author Kristin Purcell in a statement. “While they are a significant departure from search engines and web browsers, the basic needs apps meet are not revolutionary.”

The results come from a survey conducted from July 25-August 26 among 2,260 adults 18 and over, including surveys in English and Spanish and on both landline and cell phones. The margin of error for the total sample is plus or minus two percentage points.