How Duolingo Turned a Free Language App Into a $7.7 Billion Business
Language-learning app Duolingo makes around $500 million annually, despite offering all of its lessons for free. WSJ explores how the company is using AI and A/B testing to keep users hooked. Illustration: George Downs/WSJ
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The Economics Of
How do the world's most successful companies generate revenue? In this explainer series, we'll dive into the surprising stories behind how businesses work--exploring everything from Costco's "treasure-hunt" model to the economics behind Amazon's AWS.
