Facebook's Internet.org is helping carriers around the globe get more people to pay for data plans by giving them a free sample, CEO Mark Zuckerberg said Monday in Barcelona at Mobile World Congress. “These apps drive data usage," Zuckerberg said. "That is the future business, and I think that everyone is excited about that."

Internet.org is a nonprofit that was founded a few years ago by Facebook with the mission of connecting every person on the planet to the Internet. It's a long-term strategy to help Facebook grow, and over the past year, the social network has partnered with carriers from emerging markets to give customers free data for "basic services," including Facebook, Wikipedia and Google. 

"Data plans are indeed one of the key issues to connect the unconnected, more so than limited mobile penetration or coverage issues," Thomas Husson, analyst for Forrester Research, said. "Facebook's pitch is that they want to stay a partner of telcos and help them sell data plans."

That strategy has come under fire from critics who argue that Facebook is reaping new users while placing the entire burden of building, running and maintaining wireless networks on its partners. That's why Zuckerberg used the bulk of his time at the mobile conference to sing the praises of his carrier friends. 

Zuckerberg "correctly identifies that he can't do this on his own," said Telecom industry analyst Roger Entner of Recon Analytics. "He needs local partners. He needs telcos to build out the infrastructure that provides all of the connectivity. Facebook is a very rich company, but it's not able to do this on its own."

On the panel, Zuckerberg was joined by a posse of his pals from the telecom industry, including Mario Zanotti, the senior executive vice president of Latin America for Millicom, a global telecommunications giant. Zanotti vouched for Zuckerberg by saying that the introduction of Internet.org had increased his company's data users by 50 percent in Colombia in a matter of weeks while growing its number of smartphone sales in Tanzania tenfold.

"It's very good," Zanotti said. "It increased the penetration of data in the whole customer base, so there’s a whole bunch of people who didn't use any data plans who are now using, actively using, and paying.”

Following Zanotti's response, Zuckerberg gave the session one of its most memorable moments. He was asked if these were the types of results Internet.org was seeing from most of its partners, to which he answered with a very short "yeah," which was followed by awkward laughter from the panel.