Facebook advertisers are now able to buy Sponsored Stories in News Feed and on mobile separately from other ad placements by using the Ads API or Power Editor tool, the company tells us.

Previously, advertisers could not choose where their Sponsored Stories were shown, and they did not get a breakdown of performance by placement. This change will give advertisers more control over their ads and more data to be able to optimize their campaigns. For the first time, advertisers will be able to specifically indicate that they want their ads to be shown in the mobile News Feed, which presents new opportunities for app and game developers to reach Facebook users while they’re on their phones.

As seen in this image from Power Editor, advertisers can choose to show their ads in on the desktop right-hand side, desktop News Feed, mobile News Feed or all locations. This is useful for advertisers whose page or application is desktop- or mobile-only. For instance, a page seeking to drive users to a landing tab would want to promote within the desktop News Feed, but not on mobile where tabs aren’t accessible. An iOS or Android developer, however, would want to choose mobile only.

With Sponsored Stories, advertisers can only reach users who have already Liked their page or added their app, or who have friends that have connected with a page or app. Advertisers can’t specifically choose their own copy, but they can choose to promote different actions, for example, Liking a page, earning a high score or reading an article. Third-party mobile apps can then drive users to a specific section within their app or an app download page. The following story from Turntable.fm was not promoted with Sponsored Stories, but it shows the type of activity that can be sponsored and how it could drive app downloads.

Advertisers looking to promote a page or particular post might want to run different ad variations to find the best performing placement. Sponsored Stories in the feed are likely to have higher clickthrough rates than those on the right-hand side, but is too early to tell what sort of price variation there is between these different locations.

Advertisers can buy mobile or desktop News Feed placement through a third-party provider with access to the Ads API or through the Power Editor tool, but not the main self-serve ad dashboard.