Mark Zuckerberg, chief executive officer of Facebook Inc., speaks during the Facebook F8 Developers Conference in San Francisco, California, U.S., on Wednesday, April 30, 2014.
Bloomberg—Bloomberg via Getty Images
By Alex Fitzpatrick
April 27, 2016

Facebook’s stock is up nearly 9% in after-hours trading Wednesday after the company’s first quarter results obliterated analysts’ expectations.

Facebook posted adjusted earnings of $.77 per share on revenue of roughly $5.38 billion for the quarter. Analysts expected earnings of $.62 per share and $5.26 billion in revenues, per CNBC.

How is Facebook making all that money? Advertising, mostly:

Facebook Revenue Q1 2016
Facebook

But it’s the source of most of that ad revenue that’s really impressive: mobile devices, like smartphones and tablets. Facebook’s revenue from mobile advertising represented a staggering 82% of the company’s $5.2 billion in total ad revenue this quarter, or about $4.3 billion.

That’s a big deal. People are increasingly spending time on mobile devices instead of desktop computers. Just over half of Facebook’s 1.65 billion monthly active users only visit the site on a mobile device. But mobile devices represent a big challenge for advertisers, as their smaller screens offer less room for ads. Facebook, with its in-feed ads, has clearly cracked the mobile nut.

Facebook Monthly-Only MAUs
Facebook

Write to Alex Fitzpatrick at alex.fitzpatrick@time.com.

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