No, the ads are to install other mobile apps. The advertiser of the mobile app (say, for instance, Clash of Clans) only pays FB after the app is actually instal

No, the ads are to install other mobile apps. The advertiser of the mobile app (say, for instance, Clash of Clans) only pays FB after the app is actually installed on the device. For instance, on iOS, those FB mobile ads open up the Apple App Store. From there, the uesr still has to click "Install". I think it's safe to say that 99.99%+ of app installs are on purpose. No one really "accidentally" installs an app on his or her phone.