Facebook today announced it has begun testing ads in third-party mobile apps. While the company says it has experimented similarly before, this test is different because it is working directly with advertisers and publishers to act like a mobile ad network.

In other words, Facebook is working directly with its partners rather than outsourcing the work to an outside ad-serving platform. The test is limited to “a few advertisers and partners,” but Facebook hints it could be expanded in the near future.

Facebook explains why it has to move into this space to keep generating advertising revenue:

To improve the relevancy of the ads people see, provide even greater reach for Facebook advertisers and help mobile developers better monetize their apps, we’re running a small test to show Facebook ads in mobile apps. Our aim is to demonstrate even greater reach with the same power of Facebook targeting for advertisers both on and off Facebook.

This is part of a bigger strategy of focusing on mobile. Facebook not only needs to make sure its mobile apps are solid, but that it can keep up with the global shift to devices that fit into our hands.

Facebook already has Facebook Exchange, which uses cookie tracking to let advertisers bid on ads that visitors are targeted with after visiting third-party websites. These visitors are then shown ads related to their web browsing when they return to Facebook.

Yet with Twitter buying mobile advertising exchange company MoPub, Facebook needs to step up its game and make sure it can stay on top of the mobile advertising space. The company has already managed to make boatloads of money in mobile where others have failed, and third-party mobile apps only take that story further.

See also – Google partners with Facebook to help its clients buy retargeted ads via the social network’s FBX platform and Not just ads: Adblock Plus now lets you block 21 other ‘annoyances’ in Facebook’s News Feed and sidebar

Top Image Credit: Brendan Smialowski/AFP/GettyImages