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Video Duolingo is a Free, Crowdsourced Language Learning App (Video) 75

This is an interview with Duolingo engineer Franklin Ditzler. He's not a smooth marketing guy getting all rah-rah about the company and what it does, just a coder who enjoys his job and seems to like where he works and what he's doing. Note that Duolingo is a free language teaching tool, and they seem determined to keep it free for language students by selling crowdsourced translation services to companies like CNN and BuzzFeed.

Duolingo founder and CEO Luis von Ahn is an associate professor in the Carnegie Mellon University Computer Science Department, and was one of the original developers behind reCAPTCHA. Google acquired ReCAPTCHA in 2009 for "an undisclosed sum," a bit of history that led TechCrunch to speculate back in 2011 that Google would buy Duolingo within six months -- which didn't happen. But don't despair. It's still possible that Google (or another big company) might absorb Duolingo. We'll just have to wait and see -- and possibly improve our foreign language skills while we wait. (Alternate Video Link)

What is Duolingo? We are a sort of massive crowdsourced approach to language learning. Importantly, we try to be free and accessible to as large an audience as possible. We offer languages – we offer learning between many popular languages, English to many European languages—Spanish, Italian, French, German, Portuguese, with more on the way. Conversely, we do a lot of languages back to English. So the same languages can now go back to English. We have Russian to English, Chinese to English, Japanese to English, Korean to English; we have many other things that go back to English.

Tim: What are the most popular languages and what direction is it mostly?

Franklin: Spanish, English to Spanish and Spanish to English seems to be the most popular. Part of that is probably because our founder Luis grew up in Guatemala. He had a lot of influence there and he knows whom to contact I guess. I don’t know – but we do have a lot of Spanish users. I guess, next is probably Chinese to English, it is very big. I mean that’s sort of to be expected when it’s just such a big market in China.

Tim: More than a billion people.

Franklin: Yeah. More than – yeah.

Tim: When you say you want the language learning here to be accessible to a lot of people

Franklin: Yes.

Tim: Explain that a little bit—in what way?

Franklin: So first we try to be free. Unlike some other alternatives which charge hundreds of dollars, our whole goal is to try and be free. Again our founder Luis, who grew up in Guatemala, he knows about the hard life people have to live and how painful it can be when you don’t have access to language education. Especially because once you do have access a lot of doors start opening up. A lot more opportunities appear. So we really want to try and just increase the amount of people we can reach. And part of the ways we do that is by adding support from our languages. We started with some of the bigger popular languages, but we’re rapidly working on adding support for other languages that people are requesting. And the other way we do that is to try and be on many different platforms and support any different way people have with learning.

Tim: And the translations themselves are crowdsourced—is that correct?

Franklin: Yes. So as part of the learning experience you go through and you do we have a course that we make for each of these directions. They consist of little lessons, bite-sized chunks of knowledge, that are usually focused on something. So we have one that’s focused on plurals, we have one for food, animals and that sort of thing. Originally, we had a language team dedicated to making these things. But then we quickly realized that this doesn’t approach, this scale does not approach, this approach does not scale, once you start adding more and more languages.

Tim: Why don’t you back up and just say, “We realize”?

Franklin: Okay. Where should I start?

Tim: I can just ask the same question about crowdsourcing you got that right? I’ll probably rephrase it myself: Franklin, one of the ways that this is made open and free is in part through outsourcing of the exact translations, is that right?

Franklin: Yes. Our courses are made up of little skills that you go through and the skills focus on different subjects or content or just sort of sentence structure that sort of thing. So we have ones for verbs, we have some for plurals, animals, food, also sort of different things. And in those what happens is we originally had specific people, language experts who would come in and they would think about what skills we want people to learn. And then they would craft the sentences themselves. But we realized that approach doesn’t scale well, once you start adding dozens of languages. Because suddenly with every new language, it’s like an N-squared thing—that gets pretty big pretty fast. So we started developing what we call the Incubator. You can reach it at and there you can apply to be a moderator. Basically, it’s a volunteer driven system, where you can add new sentences, you can tweak existing sentences, and you can even work on building a new course if you want.

Tim: Very crowdsourced.

Franklin: Very crowdsourced. So you can add any language you can imagine. I think we have applicants for Dothraki, Klingon and Elvish—I can’t speak for the progress on those. You have to check it out.

Tim: For the accuracy?

Franklin: I can’t speak for that either. But we do get applications for all sorts of things. We try to add them as fast as people are interested.

Tim: Okay. I had another question that I have to pause here to remember what it was: Here we go so Duolingo started out on the web as a web app, and then it went from there to iOS and now to Android. So you must have an extensive background as an Android developer?

Franklin: Originally, we started on the web because originally there were just a couple of people in a small room somewhere. As we grew, we realized that there is a lot of potential if you can reach people in their everyday lives. Like on their commutes, just whenever they have a couple of minutes. And we also realized that mobile devices were increasingly prevalent everywhere in the world, I guess. So then we got an iOS developer, and he made an iOS app. Originally, we actually had a little betting pool in the beginning, about how many users we thought it would have. And we were completely off. It was crazy! Then we realized how important it was to reach these users. So we decided to also focus on Android as well. Unfortunately, we were in a little bit of a hurry so we didn’t have time to find an Android developer. So one of our existing developers, Vicki, made the first version of the Android app that launched last year May. I showed up around that time and a couple of weeks later I was doing the Android app.

Tim: Also not as an Android developer at that time?

Franklin: Not as an Android developer. So I can’t say that my code was particularly nice. I’ve learned a lot of things—it’s a learning experience. But we make do with what we can. And recently in January we hired another developer, who has never done Android before but is also now working on the app.

Tim: Three in a row?

Franklin: Yeah, I mean it worked the first time, it seemed to work the second time and hopefully will work the third time.

Tim: What kind of constraints does it impose on you to go from a web app where you have a full browser screen to a display that may be 3” x 5”, maybe a different operating system really even if it’s in the same family?

Franklin: So one of the big challenges is reducing the amount of stuff we have to show the users. It gets tricky. It’s very easy to try and squeeze too much content on a single small screen but then the user feels overwhelmed—they don’t know what to click on—it’s just a bad experience. So first we had to figure out what was the core experience we wanted our users to see, and then we tried to design around how we can make that feel the best.

In the original version, we didn’t have what we now call the tap exercise. Where you build the translation by tapping out individual words. But we quickly realized that people typing on their keyboard on a mobile device weren’t very happy—they made more mistakes, and they were less likely to do things like type out umlauts and accents and that sort of thing. So then we tried letting them tap from a word bank. Of course, there are fake words in there and incorrect options to try and throw them off. So they still have to know the correct answer. We found that throwing that in there helped a lot.

So definitely, I think the biggest thing is just how much content you can show to the user at a single point in time, and trying to reduce the influence of the keyboard—they were probably the two biggest challenges.

Tim: Has it actually changed your own language learning, outside a computer language, that is?

Franklin: My language learning? I’ve learned a little bit of German through it. Not as much as I would have liked—I had a little bit of a motivation thing. I started back in high school, I took some German classes. I think I am about up to where I was back then. But it’s also a little tricky. German has a lot of different things from English. Like now I am on genitive case—and I am going to be honest—I don’t fully understand it. But every day I try to learn a little more and one day I’ll get it, hopefully.

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Duolingo is a Free, Crowdsourced Language Learning App (Video)

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  • by rogoshen1 ( 2922505 ) on Thursday July 03, 2014 @05:14PM (#47379791)

    Google not buying them is awesome -- they'd probably shut down the service after two years, or remove support for less than popular languages.

  • My wife loves this app. I have no idea if she's actually learned anything using it, but for a while she was putting in a couple of hours every day with the language lessons.
    • by Anonymous Coward

      He doesn't suspect a thing...but I'm getting worn out.

    • Re:Wife (Score:5, Informative)

      by CanHasDIY ( 1672858 ) on Thursday July 03, 2014 @05:51PM (#47380009) Homepage Journal

      Playing with it now (phrasing, BOOM)...

      First impressions: it's cutesy fun, and the site is obviously based on the same system that Codeacademy uses.

      Two problems I've noticed thus far: 1, certain parts want you to use a microphone. I HATE websites that want to use my mic, and I'm pretty sure I'm far from alone in feeling that way.

      The other, larger issue I have is that, when you answer incorrectly, the system doesn't necessarily specify why you were wrong, which tends to lead to frustration and ultimately, giving up, since not knowing why you were wrong makes it a lot harder to know how to be right.

      Still, leaning towards the "this is pretty cool" end of the spectrum, and hopefully it gets better with time.

      • Example (Score:4, Interesting)

        by CanHasDIY ( 1672858 ) on Thursday July 03, 2014 @05:56PM (#47380043) Homepage Journal

        Just came across an example of one of my complaints:

        During the German lesson, I was asked to translate "Ein Mann trinkt Wasser." I accidentally wrote "The man" as opposed to "A man" or "One man."

        Now, since I already have a basic knowledge of the language, I knew why I was wrong immediately; but would a person who's not already familiar really learn anything from the following "tip?"

        You used the definite "The" here, instead of the indefinite "One".

        Huh? That's just confusing, especially considering that we're talking about the very first lesson in the German group; someone who is not familiar with words having different modes (i.e., most uni-lingual Americans) would find that extremely difficult to understand.


        • by xaxa ( 988988 )

          I learnt German and French at school, so I know how to learn a language, particularly European ones. I don't recall being frustrated with not knowing why I was wrong. Screenshot of the app showing the same mistake: []

          I found the mobile app really useful for learning some Spanish before going on holiday to South America earlier this year. One press turns off the microphone exercises, either permanently or for the next hour.

        • I found this app randomly about a month back, and I would echo the same criticisms. Whenever I see a sentence that needs translating the includes The/A/One (using for French, btw) I pretty much shrug and give it a crap shoot. The andriod app does allow skipping the microphone sections, though. So I don't have to call attention to myself while using it on the job by saying "I am a girl who likes apples" and getting cockeyed looks.

          All that said, the fact that this is free and I haven't hit a wall where it say

        • someone who is not familiar with words having different modes

          The problem is, that if you don't know these basic constructs in your native language then you're not really fluent in it. You might think you can speak it fluently - but you're not well enough educated if you lack the basic rules.

          Sadly this is very common: just look at all the internet content that confuses they're, their and there. Or mistakes "have" for "of" in written form.

          Perhaps Duolingo should have a qualification test to screen out people who weren't paying attention at school (as all these topic

          • That's a very of odd definition of fluency. I could be unfamiliar with the concept of intransitive verbs or genitive case and still be considered fluent in my native language. Not knowing whether to use 'there', 'their' or 'they're' in a given sentence has little to do with your knowledge of grammar and basic linguistics. If you have to analyze a sentence grammatically to correctly use 'their' in "She went to their house", you almost certainly are not a native speaker of English.

            I suspect that many people d

        • I haven't tried to german option but for spanish if the hint/tip doesn't clear it up for you there is a button for discussion about the answer. Usually the top question and answer is what you need.

      • by Anonymous Coward

        Two problems I've noticed thus far: 1, certain parts want you to use a microphone. I HATE websites that want to use my mic, and I'm pretty sure I'm far from alone in feeling that way.

        The other, larger issue I have is that, when you answer incorrectly, the system doesn't necessarily specify why you were wrong, which tends to lead to frustration and ultimately, giving up, since not knowing why you were wrong makes it a lot harder to know how to be right.

        Still, leaning towards the "this is pretty cool" end of the spectrum, and hopefully it gets better with time.

        You can change a setting to turn the parts that require the mic off.

        I agree with wanting to know why something is wrong, but the discussion on each of the questions can sometimes answer that.

      • by mjwx ( 966435 )

        Two problems I've noticed thus far: 1, certain parts want you to use a microphone. I HATE websites that want to use my mic, and I'm pretty sure I'm far from alone in feeling that way.

        1. You're not alone. I dont have a mic hooked up to my PC because I dont want websites to have access to it.

        2. Duolingo has an app for Android (I suppose they have one for that other OS that is nothing more than a minor footnote in the glorious history of Android, but who cares about them) which is the one I've used.


        • I just dont like the "do shit and get enough shit to progress" thing.

          The point is that if you know the material in question you progress quickly through it. If you do't know it you won't. If the gamification is holding you back that's because you don't know the earlier stuff as well as you think you do. You only grind when you're on a lesson with material you don't yet know.

          Like most electronic language learning aids, it can teach you vocabulary, but not how to communicate./quote>

          There's no substitute for immersion. But you have to start somewhere if you're not in a position to get immersion.

      • by Anonymous Coward

        Other problems with Duolingo is that because it is somewhat random sometimes it asks you things it hasn't told you about. For German at least it told me the answer was wrong but it had never told me the rule involved (when to use ihm or something like that). I reset the apps with a different account to be sure I hadn't just missed it, and not even in the ? extra help had it said what the rule was.

        There's nothing more frustrating than getting a question wrong because you'd never been told what the right a

      • Re:Wife (Score:4, Insightful)

        by u38cg ( 607297 ) <> on Friday July 04, 2014 @05:02AM (#47382229) Homepage
        The theory is that you are being taught as a child learns - we don't go round telling toddlers, no, Johhny, that's the dative case, not the genitive case, you silly little sausage. We just correct them by example.
        • "The theory is that you are being taught as a child learns" Bad theory. Childhood language acquisition is different from adult acquisition.
        • The thing is that that's not the most effective way to learn the basics of a second or third language.

          Second-language acquisition is a well-studied field, and at least some teaching in the learner's own language (or a language that they know well) is more effective than immersion.

          As an example, I can quickly teach you that almost all words that end in 'tion' in English are the same in French (pronunciation differs, of course), and they are all feminine, with the notable exception of 'translation'. And now y

          • by u38cg ( 607297 )
            You're probably right. They're moving in this direction a bit with the introduction comments, which I have found invaluable at times. Duolingo is also effective because it gamifies learning, producing tiny chunks and repeating them over and over.
          • Well if you'll excuse me being blunt, but that is pretty bloody obvious to the extent that you don't even really need it explained to you. Languages that are in close contact with each other share some words, what a fucking surprise. Surprise is from French by the way, and fucking is from Dutch.

      • I'm a Duikingi user myself. The mic is optional. There is also an iOS app for maintaining practice on the road.

      • by Eevee ( 535658 )

        1, certain parts want you to use a microphone.

        Hover over your name at the top of the page, select settings, and turn Microphone off.

      • The microphone parts are pretty bad. There's no obvious way to configure your mic either...
  • He's not a marketing guy.......he just has a slick website and an intro video and is doing interviews.
  • by Russ1642 ( 1087959 )

    Holy Slashvertisement Batman!

  • But after a few weeks using trying to pick up some German, I become increasingly frustrated with the app. Granted, German isn't the easiest of languages. But the app just went far too fast and failed to reinforce before moving forward. I think it's a fixable problem, but for now I'm looking elsewhere for lessons.
    • Let me know when you find a solution. I've just moved to Switzerland and would love a good app to learn a little German. I doubt I'll be learning Swiss German from an app, though...
      • I doubt I'll be learning Swiss German from an app, though...

        Any German will be better than what you already know.......

    • But after a few weeks using trying to pick up some German, I become increasingly frustrated

      Been there. Sounds like you to need to try picking up a different German.

    • by ciaran_o_riordan ( 662132 ) on Thursday July 03, 2014 @06:16PM (#47380151) Homepage

      FWIW, I'm also learning German. It's the fifth language I'm learning as an adult and it's definitely the toughest. I've never found any good software or edu-websites, I just use the old methods. I watch a lot of German telly:

      * []
      * []

      Series are the easiest because you can get to know the characters and then they're kinda predictable so you can't get completely lost. The News is easy enough because there's lots of pictures and you'll know the context of most stories, but it doesn't teach you conversational German. Comedy can be the toughest. On Das Erste, there's a crime drama most Friday and Sunday nights called Tatort which is good because there's also a version for blind people ("hÃrfassung" - o-umlaut between h and r, if that doesn't display right), which has everything of the normal version plus one extra voice describing the visuals, so you hear a lot more words.

      I also read German translations of books I've already read. And when I'm cooking I leave on WDR5 talk radio in the background, all to help develop a feel for how the language sounds when used correctly:

      * []

      And I do tandems with a native German:

      * []

      Oh, and of course I'm working my way through a book with grammar and exercises.

      Yeh, German's a tough nut to crack alright. Unlike Spanish, you have to do a lot of grammar before you can really start building sentences (the declensions are what frustrate me most) but I think it's a language where your effort won't show at first, but then there's the breakthrough later.

    • by praxis ( 19962 )

      I found that starting with several overall reviews of prior material per day and only learning a new segment of a lesson if I felt like I had mastered the prior material to be a good pace. That way I only added new words and concepts after having reiterated over the prior ones several times. I found that I had pretty good control over how quickly I added more words and concepts into my pool of learning and could control just how quickly I progressed.

  • So it's free because the product isn't the app but the user who supplies the data for Big Data to crunch.

    • by BasilBrush ( 643681 ) on Thursday July 03, 2014 @06:50PM (#47380345)

      Yes. But in this case the data the user supplies is impersonal content (translations of given texts), not personal and private information. So unlike with Google it's not a problem here.

    • Wahhh wahh wahh I want it free and no strings attached and delivered to my door and everything to be done for me me me me me!

      Of course it is free, there is no money changing hands, that is what 'free' means in this context. Free at the point of delivery. But there is a classical barter going on here. They do something for you, you in return do something for them. They aren't fucking touching you in special places, they are just encouraging you to translate some poxy sentences from one language to the other.

  • by ianezz ( 31449 ) on Thursday July 03, 2014 @07:02PM (#47380427) Homepage
    I'm trying it these days (to refresh and improve my German), and I have to say I've become sort of addicted. I can't really vouch on the quality of their courses, since the only one available for speakers of my mother tongue (English for Italian speakers) isn't that good yet (fine for most lessions, but the more advanced ones have definitively weird italian translations that could throw you off a bit). Hopefully, the courses for English speaking people are better. The web interface for the courses seems to be well-thought (lots of easy keyboard shortcuts) and works surprisingly well, didn't try the mobile applications yet.

    On the other side, for what I could see, the translations you are kindly asked to do "to repay" them are usually poorly-written descriptions of commercial articles/ads, nothing really interesting, and the related web interface has some rough spots (just some quirks, but they get distracting).

    That being said, I believe it's still the best online resource I've seen yet to get your feet wet with a foreign language (provided you know English)
  • by gabrieltss ( 64078 ) on Thursday July 03, 2014 @09:11PM (#47380977)

    I like Duolingo. I have been using it to learn Spanish (since the U.S. Government REFUSES to stop the influx of illegals!) and I LOVE how it helps you learn to learn to read, write and speak the language. I think it's a fantastic app.

    • Why should you learn Spanish? They should learn English if they come here, just like all of my ancestors did.
      • Learning an extra language expands the mind and brings new opportunities. Why would you want other people to get those benefits and not yourself?

  • by Anonymous Coward

    I've studied German using it and it's quite good. It's not going to be a one-tool-for-all-needs solution, but as a part of a well-rounded study system, I think it's very handy. However, I'm waiting til they add Russian before I really start using it regularly... which might be a while.

  • So, I actually started a language education startup called Nihongo Master, which is a startup currently aimed at teaching Japanese. I certainly looked at duolingo when I was attempting to learn Japanese on my own and it fell short similar to my thoughts on Rosetta Stone. The lack of really in-depth grammar explanation killed it for me and at the time there was little to no real social interaction and reward system; however, this has been improved with Duolingo from what I last saw. My thoughts are usuall
    • by aiht ( 1017790 )

      ... What are languages YOU want to learn?

      Japanese, actually.
      Don't read too much into that, though: I'm a self -selected sample.
      Thanks for the work you've put in. I'll have a look at Nihongo Master.

  • by pieisgood ( 841871 ) on Friday July 04, 2014 @02:11AM (#47381833) Journal

    I'd like if they supported more popular languages. Personally I'd like to learn Mandarin, but they only server European languages. I'm unsure why they don't support it. My mother speaks mandarin but I've never had the time to go out and take a college course on it, duolingo would be a great resource. Plus, Slashvertisment and what not.

    Maybe I'll try it when Eastern languages are supported.

  • by Anonymous Coward

    Duolingo is a great way to start learning a language and also contribute something back. I've been using it for the past year and have become much fluent - thanks to them! Its weak point is that while you will learn words, grammar and pronunciation, it doesn't help much at all in verbal conversation - for that I think you still need to take a course with other people. For which, I think Duolingo would go perfectly with as a secondary tool - especially the forums, which tend to provide a lot of insight to

  • by realkiwi ( 23584 ) on Friday July 04, 2014 @10:06AM (#47383353)

    Working nights in a hotel (read "lots of spare time") I decided to learn Spanish. I live 11km from Spain so it is kind of usefull... Last night a Spanish guy said I spoke real good Spanish for someone who learnt from an internet site on his own.

    I guess that is an endorsement of the quality of Duolongo lessons.

Each new user of a new system uncovers a new class of bugs. -- Kernighan