Duolingo
Duolingo is the most popular language-learning platform and the most downloaded education app globally, with over 170 million users. The company's mission is to make education free, fun, and accessible to all. Duolingo is designed to feel like a game and scientifically proven to be effective. In addition to its core platform, the company created the Duolingo English Test (DET), an affordable and convenient language certification option over 60 universities accept.