Duolingo

Duolingo (/ˌdjˈlɪŋɡ/ DEW-oh-LING-goh) is an American educational technology company which produces learning apps and provides language certification.

Duolingo, Inc.
Screenshot
Homepage
Type of businessPublic company
Traded asNasdaq: DUOL
HeadquartersPittsburgh, Pennsylvania, United States
Area servedWorldwide
Founder(s)
CEOLuis von Ahn
IndustryOnline education, Professional certification
ProductsDuolingo, Duolingo Math, Duolingo ABC, Duolingo English Test
ServicesLanguage and mathematics courses and tests.
RevenueIncrease US$369 million (2022)
Operating incomeDecrease US$−65 million (2022)
ProfitIncrease US$−60 million (2022)
Total assetsIncrease US$747 million (2022)
Total equityIncrease US$542 million (2022)
Employees600+ (December 2022)
URLduolingo.com
AdvertisingYes
RegistrationYes[lower-alpha 1]
Users60.7 million MAU (2022)
Launched27 November 2011 (2011-11-27) (private beta)
19 June 2012 (2012-06-19) (public release)
Current statusOnline
Native client(s) onAndroid, iOS, Web Browser
[1][2][3][4]

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 a wide range of language courses, teaching over 100 languages,[5] from popular languages such as English, Spanish, French, and German, to less commonly studied languages such as Welsh, Irish, and Swahili.[6] 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.[7]

The company uses a freemium model with over 500 million registered users.[8] Duolingo offers a premium service which eliminates advertising and offers more features.

History

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.[9][10] Von Ahn had sold his second company, reCAPTCHA, to Google and, with Hacker, wanted to work on something related to education.[11] 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.[12][13] Hacker (co-founder and current CTO of Duolingo) believed that "free education will really change the world"[14] 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.[15][16][17] The founders considered creating Duolingo as a nonprofit organization but Von Ahn judged this model as unsustainable.[14] 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.[18][19]

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.[20] Duolingo launched a private beta on November 27, 2011, and accumulated a waiting list of more than 300,000 people.[10][21] The platform launched to the general public on June 19, 2012, at which point the waiting list had grown to around 500,000.[22][23]

In September 2012, Duolingo announced that it had raised a further $15 million from a Series B funding round led by New Enterprise Associates, with participation from Union Square Ventures.[24] In November 2012, Duolingo released an iPhone app,[25] followed an Android app in May 2013, at which time Duolingo had a user base of around 3 million.[26] By July 2013, the service had grown to 5 million users and was rated the #1 free education app in the Google Play Store.[27]

In February 2014, Duolingo announced that it had raised $20 million from a Series C funding round led by Kleiner Caufield & Byers, with prior investors also participating.[28] At this time, Duolingo had 34 employees and reported having about 25 million registered users and 12.5 million active users,[28] though it later reported a figure closer to 60 million users.[29]

In June 2015, Duolingo announced that it had raised $45 million from a Series D funding round led by Google Capital, bringing its total funding to $83.3 million. The round valued the company at around $470 million, with 100 million registered users globally.[18][29] In April 2016, it was reported that Duolingo had more than 18 million monthly users.[30][31]

In July 2017, Duolingo announced that it had raised $25 million in a Series E funding round led by Drive Capital, bringing its total funding to $108.3 million. The round valued Duolingo at $700 million, and the company reported passing 200 million registered users, with 25 million active users.[32] It was reported that Duolingo had 95 employees.[33] Funds from the Series E round would be directed toward creating initiatives such as a related educational flashcard app, TinyCards, and testbeds for initiatives related to reading and listening comprehension.[34] On August 1, 2018, Duolingo surpassed 300 million registered users.[35]

In December 2019, it was announced that Duolingo raised $30 million in a Series F funding round from Alphabet's investment company CapitalG.[13] The round valued Duolingo at $1.5 billion. Duolingo reported 30 million active users at this time. Headcount at the company had increased to 200, and new offices had been opened in Seattle, New York and Beijing.[36]

Duolingo planned to use the funds to develop new products and further expand its team in sectors like engineering, business development, design, curriculum and content creators, community outreach, and marketing.[37]

In October 2013, Duolingo launched a crowdsourced language incubator.[38] In March 2021, Duolingo announced that it will be ending its volunteer contributor program and donating money to its volunteer contributors who helped to make Duolingo. The company said that from now on, language courses will be maintained and developed by professional linguists aligning with CEFR standards.[39] On 28 June 2021, Duolingo filed for an initial public offering on NASDAQ under the ticker DUOL.[40] From August 2021 to June 2022, the Duolingo language learning app was removed from some app stores in China.[41]

In the early 2020s, Duolingo was noted for their viral videos on the social media platform TikTok.[42][43]

In August 2022, Duolingo overhauled its user interface and user experience, changing the structure of the courses from a tree-like design where users could choose from a range of lessons after completing previous ones, to a linear progression. This was widely criticized by users across a variety of social media outlets, including Reddit and Twitter.[12] CEO Luis von Ahn said that they had no plans of undoing the changes, commenting that their decision was made in order to simplify Duolingo for new users, and that maintaining both the old and new versions would be difficult.[44]

In October 2022, Duolingo acquired Detroit-based animation studio Gunner.[45]

Services

Duolingo language app

Duolingo uses a gamified approach to language learning, with lessons that incorporate translating, interactive exercises, quizzes, and stories to make learning more engaging and fun. The platform also uses a unique algorithm that adapts to each learner's level and learning style, providing personalised feedback and recommendations to help them improve their skills.[46][47][48][49]

For some languages Duolingo offers podcasts for people in intermediate level consisting on stories told usually by native speakers from different parts of the world where the target language is spoken, but with simplified grammar, vocabulary, and with a slower intonation, as well with occasional assistance with providing context or explanations of unusual words in the source language by a narrator.[50][51]

Duolingo has been through many different phases of design. At first it provided users with different "skills" placed along a "tree", where users could progress by completing every skill above them. At any time, the user could upgrade the skill, with the final goal of turning it "golden" or "legendary". In November 2022, Duolingo switched to an AI-assisted path, where the user's learning is streamlined, without them having to make as many decisions as before.[52] Duolingo used to provide audio-only lessons for certain languages, but after the release of the new path, they were removed according to a 2022 tweet.[53]

Duolingo also provides a competitive space.[54] In Leagues, people can compete against their friends or see how they stack up against the rest of the world in randomly selected groupings of up to 30 users. Rankings in leagues are determined by the amount of XP earned in a week. Badges in Duolingo represent achievements that are earned from completing specific objectives or challenges.[55]

Duolingo provides features designed to allow teachers to track students' progress in language acquisition.

Most language-learning features in Duolingo are free of charge, but it has periodic advertising in both its mobile and web browser applications, which users can remove by paying a subscription fee or promoting referral links.[56] This feature is known as "Super Duolingo"[57] and includes benefits such as unlimited hearts (retries), level skipping, no ads, and progress quizzes.

Duolingo offers courses in the following languages:[58]

A course on Xhosa for English is in the works; it will be released in 2024.[59][60]

The Duolingo Incubator was where courses were initially developed and improved on over time.[61] It was eventually opened up for community crowdsourcing; however, it was discontinued in 2021. [62]

Duolingo ABC

Duolingo ABC is a mobile app for young children for learning letters, their sounds, phonics, and other foundational early reading concepts that was released in 2020. Duolingo ABC is free to use, and it does not contain any ads or in-app purchases. The app is available on iOS and Android devices, and is currently offered in English.[7] [63][64]

Duolingo Math

Duolingo Math is a mobile app for learning elementary mathematics in a form similar to the original app, released in October 2022. It is currently only available on iOS devices.

Duolingo English Test

Duolingo English Test (DET) is an online English proficiency test that measures a person's ability to communicate in English. The test is designed to assess a person's proficiency in the areas of reading, writing, speaking, and listening.

The Duolingo English Test is entirely computer-based and can be taken from any location with an internet connection. The test is scored on a scale of 10-160, with scores above 120 considered to be proficient in English. The test is adaptive, which means that the difficulty level of the questions adjusts to the test-taker's ability level.

One of the main advantages of the Duolingo English Test is its convenience and accessibility. Test-takers can take the test at any time, from anywhere in the world, and receive their results within 48 hours. Additionally, the test is affordable and typically costs less than other English proficiency tests such as TOEFL or IELTS.

The Duolingo English Test is recognized by many universities, colleges, and other organizations as an alternative to other English proficiency tests.[12]

Business model

Duolingo had a revenue of $1 million in 2016, $13 million in 2017,[35] $36 million in 2018,[65] and $250.77 million in 2021.[66] In May 2022, it was reported that 6.8% of Duolingo's monthly active users pay for the ad-free version of the app. Duolingo derived most of its revenue from subscription, advertising, and its Duolingo English Test.[67] In April 2020, Duolingo passed one million paid subscribers.[68] In March 2022, it had 2.9 million paid subscribers.[69]

Reception

Effectiveness

A 2017 study found no significant difference between elementary students learning Spanish through the "gamification" of Duolingo and those learning in classroom environments, with both groups demonstrating a similar increase in achievements and self-efficacy.[70]

A 2022 study on adults using Duolingo as their only language learning tool, published in the journal Foreign Language Annals, found that the participants that completed a course had similar proficiency to university students after four semesters of study. The authors therefore suggested that Duolingo could be an effective tool for foreign language learning.[71] Another 2022 study of Malaysian students learning French published by the National University of Malaysia Press found that it facilitated acquisition of vocabulary, with the authors suggesting that it was well suited for beginners in this regard.[72]

Linguist Steven Sacco at San Diego State University attempted to test Duolingo's claim that "34 hours of Duolingo are equivalent to a full university semester of language education"[73] by completing a course in Swedish, and taking a standardized elementary exam, ultimately receiving a failing grade.[74] Sacco suggested that Duolingo is helpful for learning vocabulary only in addition to immersion environments like a classroom.[74]

Awards

In 2013, Apple chose Duolingo as its iPhone App of the Year, the first time this honor had been awarded to an educational application.[75] In 2013, Duolingo ranked #7 on Fast Company's "The World's Most Innovative Companies: Education Honorees" list "for crowdsourcing web translation by turning it into a free language-learning program".[76][77][78] Duolingo won Best Education Startup at the 2014 Crunchies,[79] and was the most downloaded app in the Education category in Google Play in 2013 and 2014.[80]

In 2015, Duolingo was announced the 2015 award winner in Play & Learning category by Design to Improve Life.[81] Duolingo won Inc. magazine's Best Workplaces 2018,[82] Entrepreneur magazine's Top Company Culture List 2018,[83] and appeared in CNBC's 2018 and 2019 "Disruptor 50" lists[84][85][86] and TIME magazine's 50 Genius Companies.[87] In 2019, Duolingo was named one of Forbes's "Next Billion-Dollar Startups 2019".[88] In July 2020, Duolingo was named by PCMag as "The Best Free Language Learning App".[89]

Due to the app's sometimes aggressive sense of humor and attempts to ensure learners use it on a daily basis, Duolingo's mascot, a green cartoon owl named Duo, has been a subject of an Internet meme in which the mascot is "evil" and will stalk and threaten users if they do not keep using the app.[90] Acknowledging the meme, Duolingo released a video on April Fool's Day 2019; the video depicts a new feature called "Duolingo Push". In the video, users of "Duolingo Push" will receive reminders to use the app in person by Duo himself, who stares at users and follows them around until they use the app (in the video, Duo is depicted by a person in a large mascot costume).[91][92] On April 1, 2022, Duolingo released another video in the form of a spoof legal advertisement where the lawyers sue the company for damages due to family members going missing, once again alluding to the meme.[93]

In November 2019, Saturday Night Live parodied Duolingo in a sketch in which adults learn to communicate with children using a fictitious course on the app entitled "Duolingo for Talking to Children".[94]

See also

Notes

  1. One can use Duolingo for a few lessons before requiring an account to progress.
  2. For speakers of Spanish
  3. For speakers of Mandarin Chinese

References

  1. "Duolingo, Inc. 2022 Annual Report (Form 10-K)". U.S. Securities and Exchange Commission. 1 March 2023.
  2. "Migrating Duolingo's Android app to 100% Kotlin". blog.duolingo.com. 6 April 2020.
  3. "Real World Swift – Making Duolingo Blog". making.duolingo.com. 7 January 2015.
  4. "Rewriting Duolingo's engine in Scala – Making Duolingo Blog". making.duolingo.com. 31 January 2017.
  5. Ryan, Kevin J. (9 December 2021). "Duolingo Is Valued at $4 Billion. Here's How It Became an Overnight Success, According to Its CEO". Inc.com. Retrieved 28 February 2022.{{cite web}}: CS1 maint: url-status (link)
  6. Higgins-Dunn, Noah (14 April 2019). "If you are a 'Game of Thrones' fan, this app will teach you how to speak in High Valyrian". CNBC. Retrieved 23 May 2022.
  7. Duolingo Team (26 October 2022). "Duolingo Math makes learning easy as pi(e)". Duolingo.
  8. León, Riley de (19 November 2020). "The education app that is making equals of Bill Gates and the world's masses". CNBC. Retrieved 28 February 2022.{{cite web}}: CS1 maint: url-status (link)
  9. Siegler, M.G. (12 April 2011). "Meet Duolingo, Google's Next Acquisition Target; Learn A Language, Help The Web". TechCrunch. Retrieved 21 November 2014.
  10. "When Duolingo was young: the early years". VatorNews. 22 June 2018. Retrieved 21 December 2019.
  11. "Luis Von Ahn's answer to What made Luis Von Ahn start Duolingo? - Quora". www.quora.com. Retrieved 14 May 2021.
  12. Gifford, Bill (2 December 2022). "Can Duolingo Actually Teach You Spanish?". Bloomberg Businessweek. Retrieved 2 December 2022.
  13. "Duolingo's Luis von Ahn believes in the power of language". Mintlounge. 27 May 2022. Retrieved 28 May 2022.
  14. Olson, Parmy. "Crowdsourcing Capitalists: How Duolingo's Founders Offered Free Education To Millions". Forbes.
  15. "Online Education as a Vehicle for Human Computation". National Science Foundation.
  16. Masson-Forsythe, Heather (22 December 2022). "NSF gave Duolingo its wings!". National Science Foundation. Retrieved 25 March 2023.
  17. "Learn a language, translate the web". New Scientist.
  18. "Duolingo Raises $45 Million Series D Round Led By Google Capital, Now Valued At $470M". TechCrunch. 10 June 2015. Retrieved 14 December 2019.
  19. "Duol shareholder letter 2022".
  20. "The Daily Start-Up: Kutcher-Backed Language Site Duolingo Finds Its Voice". The Wall Street Journal. 19 June 2012. Retrieved 13 July 2012.
  21. Robertson, Adi (16 December 2011). "Duolingo will translate the internet while teaching languages". The Verge. Retrieved 3 February 2016.
  22. "When Duolingo was young: the early years". VatorNews. 22 June 2018. Retrieved 14 December 2019.
  23. Carnegie Mellon University. "Press Release: Duolingo.com Users Will Translate Web As They Learn a New Language". www.cmu.edu. Retrieved 14 May 2021.
  24. "Duolingo Raises $15M Series B Round Led By NEA, Will Expand To More Languages And To Mobile Soon". TechCrunch. 17 September 2012. Retrieved 13 December 2019.
  25. Lardinois, Frederic (13 November 2012). "Language Learning Service Duolingo Launches Its First iPhone App". TechCrunch. AOL. Retrieved 18 April 2016.
  26. "Free Language Learning Service Duolingo Comes To Android". TechCrunch. 29 May 2013. Retrieved 14 May 2021.
  27. Farber, Dan (11 July 2013). "Duolingo brings free language courses to the iPad". C net. Retrieved 21 February 2014.
  28. "Duolingo Raises $20M Series C Led By Kleiner Perkins To Dominate Online Language Learning". TechCrunch. 14 February 2014. Retrieved 14 May 2021.
  29. "100M users strong, Duolingo raises $45M led by Google at a $470M valuation to grow language-learning platform". VentureBeat. 10 June 2015. Retrieved 14 December 2019.
  30. "Duolingo Case Study – DynamoDB". Amazon Web Services, Inc. Retrieved 23 December 2019.
  31. Duolingo Stores 31 Billion Items on Amazon DynamoDB and Uses AWS to Deliver Language Lessons, retrieved 23 December 2019 via YouTube
  32. "Duolingo raises $25M at a $700M valuation". TechCrunch. 25 July 2017. Retrieved 14 December 2019.
  33. Duolingo. "Duolingo Now Valued at $1.5 Billion". www.prnewswire.com (Press release). Retrieved 14 December 2019.
  34. Elaine, Ramirez. "Duolingo Is Launching A Korean Course To Cash In On Asia's Booming Language Market". Forbes. Retrieved 11 October 2017.
  35. "Duolingo hires its first chief marketing officer as active user numbers stagnate but revenue grows". TechCrunch. August 2018. Retrieved 14 December 2019.
  36. "Duolingo raises $30 million from Alphabet's CapitalG at $1.5 billion valuation". VentureBeat. 4 December 2019. Retrieved 13 December 2019.
  37. "Duolingo touts $1.5B valuation; language company to hire 100 more people, mostly in Pittsburgh". triblive.com. 4 December 2019. Retrieved 15 December 2019.
  38. Munoz, Juan Andres (15 October 2013). "Duolingo 'incubator' aims to crowdsource language teaching". CNN. Retrieved 18 April 2022.
  39. "Ending & honoring our volunteer Contributor program". Duolingo Blog. 10 March 2021. Retrieved 7 April 2022.
  40. Sumagaysay, Levi. "Duolingo, the fast-growing language-learning app, files for IPO". MarketWatch. Retrieved 5 July 2021.
  41. "Duolingo back in China app stores after 1 year". TechCrunch. 10 June 2022. Retrieved 26 July 2022.
  42. Whateley, Dan; Mangalindan, J.P. "Meet the TikTok whisperers helping 10 top brands stand out on the app — from Netflix to Duolingo". Business Insider. Retrieved 16 August 2022.
  43. Haasch, Palmer. "Duolingo's mascot went viral on TikTok by twerking on tables and thirsting after Dua Lipa". Insider. Retrieved 16 August 2022.
  44. Goggin, Ben (25 August 2022). "Duolingo's redesign has some fans up in arms. Its CEO says it's not turning back". NBC News. Retrieved 26 August 2022.
  45. "Duolingo Acquires Detroit Animation Studio Gunner". 4 October 2022.
  46. "How we've improved the Duolingo learning experience this year (and a sneak peek toward 2020!)". Duolingo Blog. 11 December 2019. Retrieved 26 August 2021.
  47. "Everything You Need to Know About Duolingo Stories • Happily Ever Travels". Happily Ever Travels. 5 October 2020. Retrieved 26 August 2021.
  48. "Duolingo" (PDF). TESL-EJ.
  49. Agomuoh, Fionna. "I've been learning French on the Duolingo app for over a year now – here's what it's like to use the app". Business Insider. Retrieved 21 January 2020.
  50. "Duolingo Podcasts: Here's What You Need To Know". 19 November 2021.
  51. "Podcast - Duolingo". Podcast.duolingo.com. Retrieved 30 June 2022.
  52. "Introducing the new Duolingo learning path". Duolingo Blog. 6 May 2022. Retrieved 26 April 2023.
  53. "Duolingo on Twitter". Twitter. 20 October 2023. Archived from the original on 26 April 2023. Retrieved 26 April 2023.
  54. Fians, Guilherme (2021). Esperanto Revolutionaries and Geeks. London and New York: Palgrave Macmillan. doi:10.1007/978-3-030-84230-7. ISBN 978-3-030-84229-1. S2CID 245721938.
  55. Huynh, Duy; Zuo, Long; Iida, Hiroyuki (2016). Analyzing Gamification of "Duolingo" with Focus on Its Course Structure. Games and Learning Alliance. Lecture Notes in Computer Science. Springer, Cham. pp. 268–277. doi:10.1007/978-3-319-50182-6_24. ISBN 978-3319501819.
  56. "Crowdsourcing Capitalists: How Duolingo's Founders Offered Free Education To Millions". Forbes. Retrieved 22 December 2015.
  57. "Super Duolingo".
  58. "The Complete List Of EVERY Duolingo Language". Duoplanet. 17 June 2021. Retrieved 21 September 2022.
  59. "South Africa's most popular languages are coming to Duolingo". Quartz. 20 August 2021. Retrieved 7 January 2023.
  60. "Learn a language for free". Duolingo. Retrieved 5 February 2023.
  61. "What is the Incubator?". Duolingo Support. Retrieved 26 April 2023.{{cite web}}: CS1 maint: url-status (link)
  62. "Ending & honoring our volunteer Contributor program". Duolingo Blog. 10 March 2021. Retrieved 2 May 2023.
  63. "Make screentime COUNT for your kids!". teach mama. 15 September 2020. Retrieved 31 May 2022.
  64. "Duolingo ABC: Unlocking the magic of reading". Duolingo Blog. 26 August 2020. Retrieved 31 May 2022.
  65. Adams, Susan. "Game of Tongues: How Duolingo Built A $700 Million Business With Its Addictive Language-Learning App". Forbes. Retrieved 14 December 2019.
  66. 张洁. "Language-learning app Duolingo bullish on Chinese market". China Daily. Retrieved 14 December 2019.
  67. "Duolingo shareholder letter 2022".
  68. Doughty, Nate (8 April 2020). "Duolingo passes one million paid users, expands with new hires". Pittsburgh Business Times. Archived from the original on 22 January 2021. Retrieved 12 December 2020.
  69. "Duolingo Announces Record Bookings in First Quarter 2022 and Raises Full Year Guidance".
  70. Rachels, Jason R.; Rockinson-Szapkiw, Amanda J. (2018). "The effects of a mobile gamification app on elementary students' Spanish achievement and self-efficacy". Computer Assisted Language Learning. Routledge. 31 (1–2): 72–89. doi:10.1080/09588221.2017.1382536. S2CID 67064098.
  71. Jiang, Xiangying; Rollinson, Joseph; Plonsky, Luke; Gustafson, Erin; Pajak, Bozena (11 January 2022). "Evaluating the reading and listening outcomes of beginning‐level Duolingo courses". Foreign Language Annals. 54 (4): 974–1002. doi:10.1111/flan.12600. ISSN 0015-718X. S2CID 245892888.
  72. Saad, Suziana Mat; Rahim, Nur Ameera Abd (2022). "Vocabulary Acquisition Using Duolingo in French Language Learning: A Malaysian Context". E-Bangi: Journal of Social Sciences & Humanities. 19 (2): 256–281. eISSN 1823-884X.
  73. "Are there official studies about Duolingo?". Duolingo Help Center. Duolingo. Retrieved 27 April 2020.
  74. Heaney, Katie (9 July 2019). "Is It Just Me, or Does Duolingo Not Work?". The Cut. Retrieved 28 October 2020.
  75. "Duolingo snags iPhone App of the Year". Gigaom. 17 December 2013. Retrieved 21 February 2014.
  76. "The World's Most Innovative Companies 2013: Education Honorees". Fast Company. Retrieved 14 December 2019.
  77. "The World's Most Innovative Companies 2017: Education Honorees". Fast Company. Retrieved 14 December 2019.
  78. "The World's Most Innovative Companies 2017: Social Media Honorees". Fast Company. Retrieved 14 December 2019.
  79. Luis. "Duolingo turns two today!". Retrieved 21 November 2014.
  80. "Google Play reveals the most downloaded apps, games and entertainment content from 2014". The Next Web. 11 December 2014. Retrieved 29 December 2014.
  81. "Duolingo-Index: Award 2015 Winner (Play & Learning Category)". Design to Improve Life. Design to Improve Life. 27 August 2015. Archived from the original on 5 May 2016. Retrieved 28 April 2016.
  82. "Duolingo". Inc.com. Retrieved 1 August 2019.
  83. "Top Company Cultures of 2018". Entrepreneur. Retrieved 1 August 2019.
  84. staff, CNBC.com (22 May 2018). "2018 Disruptor 50: No. 35 Duolingo". CNBC. Retrieved 5 November 2018.
  85. "Duolingo: 2019 Disruptor 50 List". CNBC. 15 May 2019. Retrieved 4 September 2019.
  86. Duolingo. "Duolingo Names Gillian Munson to Board of Directors". www.prnewswire.com (Press release). Retrieved 14 December 2019.
  87. "Duolingo: The 50 Most Genius Companies of 2018". Time. Retrieved 5 November 2018.
  88. Feldman, Amy. "Next Billion-Dollar Startups 2019". Forbes. Retrieved 20 July 2019.
  89. "Duolingo Review". PCMAG. Retrieved 26 August 2021.
  90. Anderson, Sage (27 March 2019). "The Duolingo owl is out for vengeance in these threatening memes". Mashable. Retrieved 7 June 2019.
  91. Introducing Duolingo Push. Duolingo. 31 March 2019. Retrieved 7 June 2019.
  92. "How Duolingo Took over the Meme World and What Marketers Can Learn from It". rypl.io. Retrieved 7 June 2019.
  93. Lawyer Fights Duolingo Owl for $2,700,000. Duolingo. 1 February 2022. Retrieved 17 April 2022.
  94. Lee, Madasyn (5 November 2019). "Pittsburgh-based Duolingo a fan of talk-to-kids 'SNL' sketch". Pittsburgh Tribune-Review.
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