Facebook allows instant game developers to monetize their gaming apps.
It seems that, after a year of existence, Instant Games will generate revenue for their developers. Instant Games, a feature that rolled out last November and offers a fun way to connect with your friends, will now start featuring interstitial and rewarded video ads as well as in-app purchases. This ability will be tested with select game developers before being rolled out to all game developers.
This testing phase will allow Facebook to further optimise the ad platform but also help build the measurement tools that will Instant Game developers gain insightful data.
In the case that you are interesting in joining the beta programme you can sign up in the form that can be found here.