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Duolingo - The App That Changed How We Learn Languages


Luis von Ahn wanted to make learning languages easier, so he decided to create an app that would simplify the process. Since then, his app has helped millions learn new languages but also changed how people learn languages.

Duolingo enables millions of people to learn a new language for free while supporting free education at the same time. It's a tool that helps people to be better educated, giving them a better chance of landing a job.

Luis's idea that everyone should have equal learning opportunities, is an inspirational story that needs to be told.

Here's the story of Duolingo and how it came to be one of the world's most successful and used applications of our times.

An Unsung Genius

Luis von Ahn was born and grew up in Guatemala, in an upper-middle-class family.

He had attended a private English-speaking school which was a high privilege at the time.

From an early age, he was interested in computers and mathematics and he was determined to turn his interest into a fulfilling career.

He did what any ambitious high schooler would do - he went to study mathematics at Duke University. Luis was a committed student - he received his BS in mathematics in 2000 and his Ph.D. in computer science in 2005 almost effortlessly. The following year he became a faculty member at the same university, in the computer science department.

While working at the university Luis was interested in cryptography. Together with two of his colleagues, they provided definitions for stenography and they proved that private-key steganography was possible.

However, Luis became famous in 2000, for co-inventing and pioneering the CAPTCHAs, the computer generating tests that every human can pass, but computers have not yet mastered. He designed it together with Manuel Blum, a computer scientist as well as other developers as a result of a problem Yahoo! developers have come across. They noticed that their users were making programs for registering users, and there wasn't any way to stop programs from doing it.

With CAPTCHA, a program couldn't register an email address. As the internet grew so did the content on it, and CAPTCHA was a great way for new websites to make sure that real humans are the users and not automated bots or internet clones. Then in 2007, he invented reCAPTCHA which is a new form of the same program. The new program has images of words of old books in which users can find them from old digitized books. In 2009, Luis and his graduate student, Severin Hacker, began developing Duolingo, a language education platform.

The Story Of Duolingo

There were many apps for learning languages before Duolingo. Applications like Rosetta Stone or Open English were good, and they were offering around 30 languages, but there was a catch. If someone wanted to learn a new language they needed to pay for the services, which a lot of people from poorer countries couldn't afford.

So when von Luis started to develop the application with help from Hacker, their goal was to surpass the competition. The only way that they could do that was for the app to be free of charge. Living and growing in Guatemala, Luis was well aware that learning English was expensive in his country, while Severin Hacker was from Switzerland, a country where there are four national languages. This was a great mix for both of them because they were sharing a great appreciation for learning languages.

While they started to develop the application in 2009, they were quiet and didn't announce it until 2011. Even though they weren't sharing the idea with the outside world, Luis and Severin were able to get investors on the board. In the beginning, it wasn't just about the free application but to build a more sustainable way to have human translations of the web on a large scale. The duo sought this not just as a social opportunity but as a way to widen the online content.

Growing Worldwide

At first, the app only had a beta version, and over 100,000 people used Duolingo and more than half a million were on a waiting list. When in 2012 Duolingo ended the beta testing, there were lessons in four languages: German, English, Spanish, and French. The app was growing rapidly and by 2020, it had more than 300 million active users worldwide. Many users were motivated to try and learn the app because they were translating something and learning at the same time. The app was free, easy to use, and very intuitive, so millions quickly flocked to it.

Funding And Developing

Even though all that was translated was collected and it was better than a computer can do, the company didn't sell any of the content. Duolingo's developers built a software for producing a high-quality translation. The way it worked was that it would take the translation from multiple users and compare them, and will set the answer as correct if the majority of users answer the same.

After a couple of years, Luis and Severin started experimenting with companies and monetization policies. In 2013 they announced a partnership with BuzzFeed and CNN. This was very important because they started to monetize the company's services, by selling the translated content from the users. From 2014 Duolingo started a new model of monetizing using ads, and in 2017, an optional paid plan. This was a great strategy for the company because it could provide free education for all while generating revenue at the same time. If the user was not paying the optional plan, at the end of the lesson will need to watch an ad, while with the paid plan, there were no ads.

As a company, Duolingo generated millions of dollars, but the biggest surprise for Luis and Severin came from the fact that the majority of the revenue came from the paid users. Even though the minority of users are using the paid plan.

Also, it should be mentioned that from 2011 until 2020 they had seven rounds of funding in which they raised almost $150 million. That was great news for the company and the users worldwide, because now, Luis and Severin could provide more services for free.

Path To Success

Nobody can say for sure what the future holds for a company, but with its loyal customers, it's highly likely that Duolingo will continue to grow. The main reason why the company has become so popular is that it's free and easy to use.

From the beginning, they were striving to be better and more accessible service than their competitors. This meant that Luis and Severin were highly motivated to make a better product and worked around the clock to beat their competitors.

They were constantly adjusting the application and throughout the years it has become just better. How? By considering their users' feedback.

The duo's strategy for monetizing is different from that of other companies. Providing products free of charge and accumulating money from ads and paid plans is common today, but not when they started. This meant that more people were going to use the app because it was free.

New advances in tеch made it possible to target consumers and businesses with multiple products at the same time. Until now, Duolingo didn't want to do business like this but it's a common business practice for growing. Also with the funds that they've raised recently in 2020, they are planning to grow the company significantly and make a more diverse and better application for all users.


Duolingo has grown so much in the past years, and we can expect it to keep developing and providing new ways to learn languages. Luis's idea has been a great success in delivering a free application for language learning that changed the world. Even after all these years, the goal has stayed the same, free educational application for everyone.

Learning from his own experience in his home country Guatemala has motivated him to make something meaningful and good for the world. If there are more ideas like these, the world will be a better place and everyone will feel the benefits, one way or another.