One year later, Facebook has figured out mobile, experts say.
The social networking giant may have had a rough patch after its IPO, but Facebook has quickly turned things around by cashing in on its users' obsession with mobile.
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"One of the big complaints at the company's IPO was that it doesn't make any money on mobile, and that was true and fair at the time," said Jason Stein, founder and president of the social media agency Laundry Service.
Facebook had zero revenue on its mobile-ad platform when it went public but posted $375 million on mobile in the first quarter, Stein said.
"It's amazing that a company was criticized for lacking any mobile presence was able to completely build a new app and monetize it as quickly as it was able to build it," Stein said.
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Almost 70 percent of Facebook users are on the network's mobile platform, and about 30 percent of all ad revenue is generated via mobile—advertisers like that because they see huge growth opportunity, Stein said.
Eden Zoller, principal consumer analyst at Ovum, said its crucial that Facebook continue to expand into emerging markets.
"I think [ad revenue] will increase, and there's a real imperative for Facebook to continue that momentum," Zoller said. "More people are interacting with people on mobile phones, some of them on an exclusive basis. ... Facebook needs to ensure that the advertising dollars go with that migration."
Clearly, Facebook hasn't always had the right mobile approach.
CEO Mark Zuckerberg admitted in September that the company's mobile strategy had been too focused on HTML5 (the programming language that's compatible with any browser and doesn't require add-ons to function) and not enough on native apps, which users preferred.
"It completely blew up in their face, but they didn't waste any time," said Krishna Subramanian, chief marketing officer of Velti, a mobile marketer. "They got to work building very high-performing applications. They bought Instagram. They focused on mobile growth. The key thing that Zuckerberg does well is identify when things don't work and change quickly."
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The company has further boosted its mobile profile with the launch of Home, a series of apps that function as the home screen of an Android device.
Home isn't a revenue producer yet but definitely has potential, according to Stein. Home may appeal to marketers because odds of engagement with an ad increase dramatically if Facebook is always running on a user's phone.
But Home won't be a big earner for a while, Subramanian said.
"It will continue to evolve," he said. "Zuckerberg's gut feelings are very spot-on, but if you make 100 changes, not every one is going to work."
Facebook also partnered with manufacturer HTC on a smartphone, HTC First, preloaded with Home, and Subramanian said he could see the company taking on more hardware partnerships.
"You don't just go out and build a phone—you focus on what your core strengths are," he said. "I could see them building an OS to power devices or deeper integrations" on platforms.
"I definitely think things are going in the right direction," Subramanian said. "I'm definitely excited about what they are doing from a mobile-ad perspective and excited to see how they drive the connected consumer."
—By CNBC's Cadie Thompson. Follow her on Twitter @CadieThompson.