Paytm's Vijay Shekhar Sharma, India's youngest billionaire on Forbes's World's Billionaires List

“Two thousand seventeen will be ours! How could it not be?” Paytm CEO Vijay Shekhar Sharma, lit by spotlights and shouting into his microphone to wild applause at his mobile-payments startup’s annual party in January, had reason to celebrate. Paytm is cashing in big on India’s move away from paper currency, minting Sharma, 38, as India’s youngest billionaire.

Backed by Alibaba, Paytm began as a simple mobile wallet and has expanded into a platform for buying groceries, booking flights, paying electric bills and more. When PM Narendra Modi suddenly took 86 percent of the country’s paper currency out of circulation last November—an attempt to crack down on tax evasion and money laundering—Sharma recognised an opportunity. Paytm launched an ad campaign and rolled out versions of its app in 11 languages, hoping to bring Paytm into rural India. It worked: The platform’s number of daily transactions doubled to 5 million within 10 days and has since risen to 7 million. In February, Paytm hit 200 million users, up 64 percent from January 2016. Sharma’s next project is an online-payments bank. “We are on a mission to change this country for good,” he says.