Duolingo

Duolingo (ˌdjuːoʊˈlɪŋɡoʊ ) is an American educational technology company which produces learning apps and provides language certification. The platform was founded in 2011 by Luis von Ahn and Severin Hacker and has since grown to become one of the most popular language learning apps in the world. Duolingo offers over 40 different language courses, from popular languages, such as English and Spanish to less commonly studied languages, such as Welsh, Irish, and Swahili. Duolingo also offers the Duolingo English Test certification program and a literacy app for children called Duolingo ABC, and the company released an elementary level math app called Duolingo Math currently exclusive to iOS. The company uses a freemium model with over 500 million registered users. Duolingo offers a premium service which eliminates advertising and offers more features. The idea for Duolingo was initiated at the end of 2009 in Pittsburgh by Carnegie Mellon University professor Luis von Ahn and his Swiss-born post-graduate student Severin Hacker. Von Ahn had sold his second company, reCAPTCHA, to Google and, with Hacker, wanted to work on something related to education. A driving motivation was Von Ahn's upbringing in Guatemala, where he saw how expensive it was for people in his community to learn English. Hacker (co-founder and current CTO of Duolingo) believed that "free education will really change the world" and wanted to supply people an outlet to do so. The project was originally sponsored by Luis von Ahn's MacArthur fellowship and a National Science Foundation grant. The founders considered creating Duolingo as a nonprofit organization but Von Ahn judged this model as unsustainable. An early revenue stream was as a crowdsourced translation service. This was replaced as a source of revenue by a Duolingo English Test certification program, advertising and subscription. In October 2011, Duolingo announced that it had raised $3.3 million from a Series A round of funding, led by Union Square Ventures, with participation from author Tim Ferriss and actor Ashton Kutcher's investing firm A-Grade Investments.