11/22/2010 09:16 am ET Updated May 25, 2011

The 15 Most Popular Facebook Apps Ranked By AppData (PICTURES)

Based on figures gathered by AppData, we've assembled a list of the 15 most popular Facebook applications, ranked by the number of monthly active users.

While games dominate the list of Facebook's popular apps, there are a few surprises, such as an instant messenger and a forum for activists to share their ideas. Interestingly, many of the apps on this list were also listed among the apps caught handing over their users' Facebook ID numbers to third parties.

Check out our slideshow of top apps (below), and vote for your favorite. Do any of these figures surprise you? What's your favorite Facebook app? Let us know in the comments. Then, view our slideshow of apps that gave up users' personal information.