If you want to learn to talk like the characters in the HBO hit series "Game of Thrones," there's an app for that.
Duolingo, No. 28 on the 2019 CNBC Disruptor 50 list, offers online instruction of High Valyrian. It is one of more than 30 languages the app provides for free.
And it should come as no surprise that one of the languages created for "Game of Thrones" is among Duolingo's more favored options.
"High Valyrian is very popular of late, particularly with the last season of 'Game of Thrones,'" Duolingo CEO Luis von Ahn said in an interview with CNBC's "The Exchange" on Friday.
"The person who created the language for HBO is … the only fluent speaker of High Valyrian... David Peterson," added von Ahn. "He decided to help us add the language to Duolingo."
The move has paid off — High Valyrian is more popular on the app than some languages spoken in the real world, like Irish, Polish or Hebrew.
"I don't know what to think about the fact that there are more people learning High Valyrian than Irish, but it is happening," von Ahn said.
Duolingo, founded by von Ahn and Severin Hacker in 2011, aims to teach languages in short lessons that are more like a game.
They went that route in an effort to engage their users.
"Learning a language is a lot like going to the gym. Everybody kind of wants to do it, but it requires a lot of effort doing so and sticking with," von Ahn explained.
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Some of the "gamification" features include accumulating points every time you use it.
"There is a lot of different aspects of it, animations and everything, that makes it really feel like you are playing a game, which is what keeps people addicted," he said.
The 150-person company says it has more than 300 million users on its platform and reached $36 million in revenue last year through a combination of advertising and paid services.
