Most web publishers are seeing more than half of their traffic coming from readers who are on mobile devices, but so far the advertising dollars have not kept up with the shift to digital, even less so with the shift to mobile. That is, until now.

In Facebook’s impressive earnings report from Q2 2014 released yesterday, it was revealed that revenue was $2.91 billion, up 61 percent from $1.81 billion during the same period last year. What’s more, nearly two thirds of those revenues came from mobile ads. It represents a wide gap in favor of mobile and illustrates that a fundamental shift is not just under way, but has already happened. So what finally made the difference

According to the ad exchange OpenX, more than half of the effective mobile campaigns are now being delivered in a native format. With banners ads proven ineffective on the web and even less so on mobile, Facebook pioneered this format which allows advertisers to present their marketing messages in a less intrusive manner in the news stream with the same look and feel “in-stream”.

Native is the “killer app” that advertisers were waiting for in order to shift serious ad dollars over to mobile. Facebook is already banking a lot of those mobile dollars with company operating margins at 48 percent in the second quarter. They are now focusing on getting native right on other platforms such as Instagram as well.

We can expect similar advertising results from other publishers as they trim and tweak their own “in-stream” ad offering.