Tech's Best Young Entrepreneurs

Jia Shen, 28

Company: RockYou

Funding: About $15 million from Sequoia Capital, Partech International, and Lightspeed Venture Partners

RockYou co-founder Shen likes to boast about his company's speed. RockYou makes software that helps Internet users add pizzazz to social network profile pages. Last year the company introduced Superwall, a feature that lets users post video and other content to friends' pages, three days after dreaming it up, says Shen, Rock-You's CTO. Now he'll need to make sure that a hiring binge—which has doubled headcount, to 40, since November—won't inhibit RockYou from keeping up with its better-funded rival, Slide. "You don't want to lose that edge," he says. Meantime, RockYou is lining up a new round of funding to stay sharp.

Advice: "We've never been extravagant in the way we spend money," Shen says. "Every person we hire is for a specific use. When we bring a person in, we know we can bring in more unique users and more page views."