Facebook introduced a new type of ad called mobile app install ad. It would appear on the mobile news feed, would take users to the App Store or Google Play page for that app. Now it looks like Facebook might be bringing more ads to its mobile app.
Like mobile app install ads, the new notifications tab ads will presumably take the user to the App Store or Google Play page for the game in question. All Things D says the ads are based upon your previous play history, and those who don’t play games will not see the ads.