Facebook reported its first-quarter earnings today, posting revenues of $2.5 billion and a profit of $1.07 billion in profit. That's a big improvement over the same quarter last year, when it reported $1.45 billion in revenues and $373 million in profit. That means in the last year revenue was up 72 percent and profit roughly tripled.

One of the numbers that really stood out was how much Facebook makes per user. In the US and Canada Facebook now makes $5.18 in annual advertising revenue per user. That's an increase of over 80 percent from one year ago.

After the raw financials, an important metric investors watch with Facebook is the number of active users, both on desktop and mobile. The company reported 1.28 billion monthly active users and over 1 billion monthly active mobile users. This time last year Facebook had 1.1 billion active monthly users and 751 million monthly mobile users, an increase of 34 percent. It was the first time it had over 1 billion mobile users in a single month.

1.28 billion monthly active users and over 1 billion monthly active mobile users

One of the big knocks on Facebook as it prepared for its IPO was that its business was still focused on the desktop while its users were migrating to mobile. The company has turned things around since then, and last quarter reported that more than half its revenue came from mobile ads. This quarter it made 59 percent of its advertising revenue on mobile, compared to around 30 percent one year ago.

On the mobile front, Facebook paid a whopping $19 billion for WhatsApp this quarter. During today's earnings call Facebook CEO Mark Zuckerberg said that he thought "WhatsApp could be as ubiquitous as Facebook one day." At the same time he noted that there were no plans to monetize this acquisition yet by opening it up to advertising, but instead to focus on getting it to a billion users. He also said it doesn't cannibalize Facebook's existing user base. "WhatsApp and messenger are growing independently because they have different use cases," said Zuckerberg.

"WhatsApp could be as ubiquitous as Facebook one day."

Not everyone was excited about today's Facebook earnings. Nate Elliot at Forrester Research said that, "Today was most notable for what Facebook didn't say: They didn't given an update on teen usage, they didn't announce video ads, and they didn't announce a mobile ad network."

The company also announced David Ebersman, its chief financial officer, will be stepping down. Ebersman helped guide the company through its troubled IPO and its recent strong showing over its first few quarters as a public company. He will be replaced by David Wehner, the former Zynga CFO, who has been Facebook's number two finance executive.