Duolingo

Language-learning app that uses short, gamified lessons to help users practice vocabulary, grammar, listening, and speaking in an engaging way.

Website: https://www.duolingo.com/

Source of images: official website

Function: Digital language-learning platform for self-paced learning focused on practical communication.
Educational context: Higher Education, VET, Lifelong Learning, Self-study
AI feature: AI-powered conversational practice and personalized feedback through features like Roleplay, Video Call, and answer explanations.

Platform: Web and mobile platform (iOS, Android).
Cost: Free basic version; paid subscriptions available with Super Duolingo and Duolingo Max plans.
Data & privacy: Privacy settings allow users to manage personal data, cookie preferences, and advertising choices, with data collected to support learning, personalization, and service improvement.

Tool characteristics

Duolingo is a digital language-learning platform designed to support self-paced and autonomous learning through short, interactive, and gamified lessons. Its main goal is to make language study accessible, engaging, and easy to integrate into daily life. The platform helps learners develop vocabulary, grammar, listening, pronunciation, and reading skills through a wide variety of exercises based on repetition, gradual progression, and active practice. Features such as points, levels, streaks, and rewards are used to increase motivation and encourage regular use.

Duolingo is particularly suitable for self-study, lifelong learning, and informal language practice, but it can also be used as a complementary resource in Higher Education and VET contexts. It is available on web and mobile devices, which makes it flexible and accessible for different types of learners. In addition, some premium features include AI-based tools for conversational practice and personalized feedback, helping users experience more interactive and realistic language learning. Overall, Duolingo is widely recognized as an effective and user-friendly platform for independent language practice.

Duolingo helps learners practice basic language skills through a wide range of controlled and interactive activities. Speaking is developed through repetition, pronunciation practice, and, with Duolingo Max, simulated verbal interaction through Roleplay and Video Call. Listening is trained through exercises such as listen-and-choose, dictation, slow playback, audio-text matching, and short stories with comprehension questions. Reading activities are mainly based on short dialogues, paragraphs, and mini-stories, while longer texts are limited.

Writing practice in Duolingo is mostly sentence-based rather than extended or open-ended. Learners work on translation, dictation, fill-in-the-blank tasks, and short written responses in stories. In many cases, they can type answers directly instead of using word banks, which makes writing practice slightly more authentic. Overall, Duolingo focuses on accuracy, repetition, and guided practice rather than free production.

Machine learning and generative AI (including GPT-4) for adaptive learning, conversational practice, and personalized feedback.

Duolingo offers courses in 40+ languages.

English is the source language for 40 languages. Several language combinations are available.

List of available courses: https://www.duolingo.com/courses/all

The features Explain My Answer and Roleplay in Duolingo Max are available to English speakers learning French, Spanish, German, Portuguese, and Italian. They are also available for English for Spanish speakers, English for Portuguese speakers, English for Japanese speakers, English for German speakers and English for French speakers.

The AI-based features in Duolingo Max provide instant feedback and explanations in the feature Explain my answer. Learners can ask questions and get tips and insights in specific exercises. Roleplay allows learners to practice real-world conversation skills with characters in the app. They encounter different scenarios with each character (e.g. ordering a coffee with Linn). These features are only available in certain languages. Video call with Lily: learners can practice their conversational skills with on-demand video calls with the Duolingo character Lily.

Duolingo for Schools provides teachers with teacher guides on how to integrate Duolingo in language classes.

Link to teacher guides; https://schools.duolingo.com/professionaldev

Duolingo supports both learners and teachers through a combination of AI-based features and classroom management tools. For learners, Duolingo Max enhances the learning experience with instant feedback, answer explanations, and interactive conversation practice. Through Explain My Answer, learners can ask questions and receive tips and insights on specific exercises, while Roleplay and Video Call with Lily allow them to practice real-life communication in simulated scenarios with app characters. However, these AI-based features are currently available only for selected languages. For teachers, Duolingo for Schools provides guides and professional development resources to help integrate the platform into language classes, as well as tools to track student progress, monitor performance, set class goals, assign general tasks, and use standardized progress metrics. At the same time, teachers have limited control over the specific content students complete, since the learning path is mainly determined by Duolingo’s internal algorithms rather than by teacher-defined lesson content.

Duolingo includes formative assessment and spaced repetition throughout its learning path. Learners receive immediate feedback on each exercise, while the hearts system tracks mistakes and encourages greater accuracy and review. When errors occur, the platform adapts by scheduling repeated practice on weak items, supporting reinforcement over time. Additional assessment elements include checkpoint tests, unit quizzes, and comprehension questions in stories and listening/reading activities, all designed to confirm progress and understanding. Gamified indicators such as XP and streaks also help reflect learner consistency, although they are not formal assessment tools. In addition, the Duolingo English Test is an adaptive online proficiency test that assesses reading, writing, speaking, and listening, with scores ranging from 10 to 160.

For teachers, Duolingo for Schools provides progress-monitoring tools that allow them to track student activity, including XP earned, time spent, completed skills, recurring errors, and areas where additional practice is needed.

Duolingo offers a relatively flexible and accessible learning environment for students with different needs and learning preferences. In terms of accessibility, it supports screen readers such as VoiceOver on iOS and TalkBack on Android, includes options that improve readability such as high-contrast display and larger text, allows users to reduce motion and animations, and provides text-based support and subtitles that can benefit hearing-impaired learners. Flexibility is also a key feature of the platform: learners can access Duolingo on different devices, including smartphones, tablets, and computers, and can adapt study pace through daily goals and self-managed routines. The platform also adjusts to learner performance through adaptive review, checkpoint tests, unit quizzes, and comprehension activities in stories and listening/reading tasks, while XP and streaks offer additional indicators of consistency and engagement. Beyond the learning app, the Duolingo English Test provides an adaptive online assessment of reading, writing, speaking, and listening proficiency in English.

For teachers, Duolingo for Schools offers progress-monitoring tools that make it easier to follow student activity and performance. Teachers can view data such as XP earned, time spent, completed skills, recurring errors, and areas where learners need more practice.

Duolingo states that it follows measures for privacy and personal data protection, including GDPR-related rights for users in the EU/EEA. The platform explains that it collects personal data, such as account information and usage data, and allows users to access, correct, or delete their data.

For speaking exercises, Duolingo may collect speech data to improve its speaking features. However, it states that this data is collected anonymously and is not linked to identifying information. Users must give permission and can turn off speech data collection. Speech data from children is handled with special care.

Users can delete or deactivate their accounts, and in Duolingo for Schools some data is not retained after account deletion. Duolingo also declares that it uses technical and administrative safeguards to protect the confidentiality, integrity, and availability of personal information.

Target Group

Features

Duolingo supports the development of all language skills from level A1 to level B2, according the CEFR. However, its focus is on core vocabulary (high frequency words), grammar (basic sentence reading, listening recognition of set phrases), pronunciation, and spelling. Speaking fluency, extended writing, real-time conversational skills, and cultural/pragmatic use of language are weakly supported. Interactional recourses to develop communicational skills are limited and are only offered in Duolingo Max.

Teachers can use Duolingo for language drilling activities to enhance students’ language skills and language proficiency. From the exposure to Duolingo’s learning path they can get insights into graded input, repetition, and progression. They can also develop teaching skills regarding assessment and feedback when looking at how Duolingo handles instant correction, streaks, and progress checks. Concerning reading and listening activities, Stories and Podcasts show how to scaffold comprehension with visuals, questions, and graded input. In Duolingo Max, Explain my answer shows how to clarify mistakes, and Roleplay how to scaffold conversation tasks with AI.

Duolingo is not specifically designed for this professional category. It does not train specialized translation or interpreting skills, so it should be considered only a complementary language practice tool.

However, Duolingo can support translators and interpreters by improving general language skills such as vocabulary, grammar, listening, reading, and pronunciation.

Gamification as means of engaging learners to practise the language daily can lead to habit formation. The short lessons also make it possible to fit them into the learners’ daily routines. The adaptive learning path (repetitions where needed, AI-driven difficulty scaling) makes tasks not too easy and not too difficult, i.e. keep learners in the “flow zone”. The playful design can lower anxiety and encourage risk-taking in language practice. However, learners can also refuse this design which makes it counterproductive.

Duolingo is not specifically designed for translators and interpreters.
It is mainly intended for general language learners and supports basic to intermediate language practice rather than professional translation or interpreting skills.

Engagement is high thanks to gamified activities and continuous progress tracking, but Duolingo is not specifically designed for translators and interpreters.

It is easy to get access to the free version and to use its functions. Some instructions are unclear.

It is easy to use the tool, however Duolingo’s use might be constrained by institutional policies and privacy issues.

Duolingo is not designed specifically for translators and interpreters. However, it is easy to use thanks to its simple interface, short exercises, clear instructions, and immediate feedback for general language practice.

Concerning technical reliability, the free version and Super Duolingo are stable, there are occasional bugs. Duolingo Max is less reliable due to the reliance on generative AI (Explain my Answer may oversimplify, Roleplay may generate odd responses).

Concerning pedagogical accuracy, vocabulary, grammar, and pronunciation are largely correct. Text-to-speech voices lack natural rhythm and accent variety; speech recognition is unreliable and forgiving. Weaknesses in terms of pragmatic language use. Learners may not learn what is socially appropriate in real-life settings.

Reliability and accuracy are adequate for learner practice, progress monitoring, and classroom support, but more limited for fully customized instruction. Duolingo provides consistent feedback and standardized learning paths, yet teachers have limited control over specific content and learning sequences.

Duolingo is not specifically designed for translators and interpreters. Its accuracy is useful for basic practice, but not reliable enough for professional translation or interpreting tasks.

Duolingo states that Max uses OpenAI’s GPT-4 for explanations and roleplay. This is clear in press releases and blog posts. Regular learners don’t see much about how the adaptive path or spaced repetition decisions are made. It’s presented as a “magic path” without explanation. Learners aren’t told what criteria the AI uses to judge pronunciation — only “correct” or “try again.” Users know their data is tracked (progress, mistakes), but not how it’s modelled or weighted in AI decisions.

Educational Transparency: Teachers (via Duolingo for Schools) see progress dashboards, but they don’t see why the AI made certain choices (e.g., why a review popped up).

AI explainability is limited. Duolingo offers some answer explanations, but it does not provide detailed transparency on how its AI systems work or make decisions.

Duolingo supports procedural autonomy (when, how long, where to study) but not much content autonomy (what or how to learn). Very little control over content order (new “path” system is linear). Learners can’t choose communicative tasks → autonomy in how to learn is low. Duolingo Max is a step forward in reflective autonomy (self-understanding of errors). “Roleplay” allows semi-free interaction with AI, closer to self-directed practice. However, conversations are still scripted; learners can’t fully set learning goals or themes.

Duolingo may foster individual autonomy, but not pedagogical autonomy. Teachers have little influence over how the app develops autonomy, and learners rarely reflect on strategies — they just “play the game.” Teachers may see learners working independently with minimal guidance. However, autonomy may become isolation and there is no collaborative or peer-directed autonomy. Teachers play no teacher role in shaping learner autonomy beyond app usage.

High for self-paced language practice, but limited for professional translation and interpreting, as it is not specifically designed for this category.