For some Silicon Valley start-ups, it's lately popular to build a user base and worry about monetizing later. Social trivia gaming app QuizUp, however, has been able to find explosive growth while simultaneously monetizing.
The recipe? Let users play for free and monetize through business partnerships.
QuizUp, developed by Plain Vanilla Games and released for iPhone last November and Android this past March, said it's on track to pass 20 million users this week.
QuizUp founder and CEO Thor Fridriksson told CNBC's "Power Lunch" it has been a "fairy-tale" ride.
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By accepting the challenges of mobile ads during user experience, he said the company was forced to think outside the box with its revenue model.
"We're purely mobile now. We really don't like those mobile advertisements, those banners and full-screen ads that always seem to be tricking you somehow," he said.