Facebook (NASDAQ:FB) impressed investors with its second-quarter earnings, thanks in large part to its mobile ad business soaring to account for 41% of ad sales. That translates into over $655 million in mobile ad revenue last quarter. That figure was just 3%, or $30 million, a year ago. Facebook just grew its mobile ad business by 22-fold

In the video below, Fool analysts Evan Niu, CFA, and Eric Bleeker, CFA, discuss how impressive Facebook's quarter was and how the company is proving its ability to monetize mobile users.

The relevant segment can be found between 0:00 and 4:26.

Chris Hill has no position in any stocks mentioned. Eric Bleeker, CFA, has no position in any stocks mentioned. Fool contributor Evan Niu, CFA, has no position in any stocks mentioned. The Motley Fool recommends Facebook. The Motley Fool owns shares of Facebook. Try any of our Foolish newsletter services free for 30 days. We Fools may not all hold the same opinions, but we all believe that considering a diverse range of insights makes us better investors. The Motley Fool has a disclosure policy.