A year ago, Facebook launched mobile app install ads, and today, they get video support and the ability for developers to set cost per action bids.

Video ads will appear in the mobile news feed when the user clicks the play button. They can then view video featuring the app, which gives developers the chance to try and sell them on it.

“Video creative has proven to be an effective way to drive engagement in News Feed, and we look forward to helping developers use their video creative to find new app installs,” says Facebook’s Radu Margarint in a blog post.

He shares the following quote from John Clelland, VP, Interactive Marketing at DoubleDown Casino, an early test partner for video mobile app ads:

“In our early tests, we found that using video in our mobile app ads resulted in increased install rates and decreased costs per install. We’ve seen tremendous success with mobile app ads and are looking forward to using video to make them even more engaging with rich media like video.”

In the past, Facebook has only let advertisers bid on cost per click or optimized cost per impression, but now, they can set a cost per action bid, so they’re only charged when a user downloads and installs their app.

According to the company, this drives a 20% lower cost per install compared to CPC (on average, based on internal testing).

Both video creative and CPA buying will be rolling out over the next few days.