"It was incredible," says DÃaz, who later moved the company's headquarters to Sunnyvale, Calif. "They gave us $50,000, which is just what we needed."
Since then, Yogome has created 11 more app-based games that have been downloaded more than 4 million times in 157 countries. Popular games like Science Heroes and Holidays Recycle Heroes, which are available in English and Spanish, helped rank Yogome as one of the top 200 publishers of free education apps for Apple devices, according to analytics for the first quarter of 2014.
The company's steady growth recently spurred another round of investment—$750,000—from a handful of donors and investors in Silicon Valley. A portion of that money now pays the salaries of Yogome's five American employees in California and 15 game developers in its Mexico City office.
But there's a problem: ColÃn and DÃaz can't live or work in the United States. They don't have work visas. They can visit and raise capital in California on a visa for business visitors, but DÃaz must leave his Sunnyvale office every six months. He collects his company salary in Mexico.
Getting U.S. work authorization is a huge challenge for foreign entrepreneurs who are increasingly starting businesses in America's tech capital. DÃaz hopes to get a temporary work permit through the North American Free Trade Agreement, which grants visas to certain professionals from Mexico and Canada. "Registering my business in the United States was the easy part. Getting paid a salary is another thing," DÃaz says over the phone from his office in Mexico City, where local schoolchildren often stop by to test out new games.
Still, it's not an option to move the company out of Silicon Valley. Tech start-ups could never thrive in places like Mexico, DÃaz says. The tech community there is too small and investors would rather fund safer ventures, such as real estate projects. "In Silicon Valley, it's all about risk," says Diaz, who hopes to raise a family in San Francisco or Palo Alto one day. "Facebook would never have happened in Mexico."
Diaz credits his parents, who run a heavy-equipment repair shop in San Luis PotosÃ, Mexico, for encouraging him to take chances. They bought him a computer, magazines, and instructional CDs when he first showed interest in computer programming as a teenager. He later got a scholarship to study computer engineering at the San Luis campus of Mexico's prestigious Universidad Tecnológico de Monterrey.
He and ColÃn began their own business by building websites for other small businesses. Before long, the two were designing online math games for a local kindergarten. That's when they realized they could make more money selling the games directly to consumers who use smartphones and tablets. In one weekend, DÃaz learned to make games for iPads. Then he hired academic experts to develop educational content. "It was the best decision we ever made," says DÃaz, who got Yogome started with $10,000 from relatives and $20,000 from a small Silicon Valley fund for Mexican start-ups.