Which Android apps are the most popular?

Breaking down the results by age range, Nielsen found that Android Market was the top app--not surprising, since that's where most Android users go to find their favorite apps in the first place.

But in second place was Facebook, popular among 80 percent of those 18 to 24 years old, 81 percent of those in the 25-to-34 bracket, and 77 percent of those 35 to 44.

From there, the results varied based on age. However, Google found its apps among the most popular, with its search app, Gmail, Google Maps, and YouTube taking top spots.

Below Facebook and Google in the list of Android app popularity rankings, one sees a variety of other categories, including entertainment, games, and productivity software.

Pandora Radio was popular among 30 percent of those 18 to 25, while Angry Birds was a favorite among 29 percent of people 25 to 34 and 35 percent of those 35 to 44. QuickOffice was midway down the charts among the different age groups.

Drilling further down the list, apps for Adobe Reader, Yahoo Mail, The Weather Channel, and Advanced Task Killer Free were also favorites. And in a sign that Google's Android Market isn't the only game in town, Amazon's Appstore for Android was favored by the three different age groups.

To rank the popularity of Android apps, Nielsen looked at the percentage of people who used them over the past 30 days. The data was taken from meters on the smartphones from thousands of consumers who have volunteered to be part of Nielsen's ongoing Smartphone Analytics research.