Mobile phone advertising and penetration are expected to grow significantly in Africa in the next few years.

Research company eMarketer says 671 million people in the Middle East and Africa will use mobile phones by 2017, up from 526 million in 2013, according to a New York Times report. Spending on digital advertising in the region is expected to reach $3.8 billion by 2017, up from $1.3 billion in 2013.

Peter Bale, digital vice president at CNN International in London, wanted to know how Africans would react if the pope were from Africa. CNN International receives a “very significant amount” of its digital traffic from its African consumers through their mobile devices, the report said, so using a mobile survey platform made sense.

Instead of going to social media, Bale used Jana, which pegs itself as the world’s largest rewards platform. Jana says it is integrated into the billing systems of 237 mobile operators and can instantly reward 3.48 billion emerging-market consumers in 70 local currencies with prepaid airtime. Consumers are rewarded for actions including registrations and app downloads, uploading photos, referring a friend or buying a product. With every action that it rewards, Jana gathers data about consumers and their behavior.

Within days, Bale had surveyed 20,000 Africans in 11 countries. Companies that have used Jana include Microsoft, Johnson & Johnson, Unilever, Procter & Gamble and Google.

Paris-based Publicis Groupe, one of the world’s largest advertising holding companies, plans to announce a $15 million investment in Jana, the New York Times reports. The investment is the first by the company in a mobile technology start-up. As part of the investment, Publicis CEO Maurice Lévy will join the board of directors at Jana.

“It’s not surprising that companies are sensing tremendous opportunity in … Africa,” said Clark Fredricksen, vice president for communications at eMarketer. “To get a foothold now in an early stage in a small market could mean a dramatic high growth for the next decade or more as that market becomes more mature.”

The potential for growth in emerging markets piqued interest in the possibility of a Publicis investment, said Todd Dagres, founding partner of Spark Capital, a venture capital company that was an early investor in Jana and social media companies like Tumblr, Twitter and Foursquare, the report said.

“It became clear to us that it would be helpful to have a partner that had relationships to the advertisers and understood on a global basis advertising and research,” Dagres said.

In a phone interview, Lévy said, “Everyone is fighting very hard and trying to find solutions to get these next billion consumers, and we all know the next billion consumers will come from emerging markets…Gaining access to consumers in Africa…is not something which is just wishful thinking.”