Subversive

How Duolingo Built Duolingo Max

Apr 16, 2025

Natalia Castillejo, Director of Product at Duolingo, has been instrumental in the development of innovative features like Duolingo Max. She shares insights on how AI-driven functionalities like video calls and personalized feedback revolutionized language learning. Discussing her journey from intern to director, Natalia highlights the importance of user-centric design and A/B testing in product development. She emphasizes that successful monetization requires understanding user needs, paving the way for engaging educational experiences.

49:49

Episode guests

Natalia Castillejo

AI Summary

AI Chapters

Episode notes

Podcast summary created with Snipd AI

Quick takeaways

Duolingo invested in AI features starting in 2022, enhancing user engagement through personalized experiences and interactive conversation tools.

The successful launch of Duolingo Max relied on repositioning it to emphasize conversational learning rather than simply offering AI capabilities.

Deep dives

Development of AI Features

The introduction of AI features at Duolingo began in late 2022 when the team gained early access to advanced language models like ChatGPT. This technology enabled the team to create personalized feedback mechanisms and interactive conversation features, enhancing user engagement in language learning. The launch of these features has significantly transformed how users interact with the app, moving from static content to dynamic, responsive experiences tailored to individual needs. The combination of improved features and the implementation of video calls contributed to a notable increase in subscription monetization, solidifying the value of Duolingo Max.

Intro

2min

From Intern to Innovator: The Duolingo Journey

18min

User Research Insights and A-B Testing Strategies

2min

Enhancing Product Management Efficiency with AI Tools

3min

The Impact of Video Call Features on User Engagement

2min

Navigating Duolingo's Subscription Landscape

20min

The Poetics of Language and Subscription App Preferences

2min

The Evolution of Online Education and Personal Connections

2min

Natalia Castillejo is a Director of Product at Duolingo, where she has spent the last decade since graduating from Yale University in 2016. Natalia started her PM career at Duolingo working on the company’s English Language Test and other core product features. More recently, she helped lead the development and monetization of AI-powered features like “Video Call,” “Roleplay,” and “Explain My Answer” that form the core of Duolingo Max, and then transitioned from core product to monetization to help accelerate the growth of this new higher-priced subscription tier.

Key Takeaways:

Duolingo started investing in AI product features in 2022 after getting early access to ChatGPT. It spent a year building and refining these features before packaging them into its new higher-priced Duolingo Max subscription tier in 2023.
Duolingo Max wasn’t an overnight success. It wasn’t until the company launched video calls and repositioned Max from “pay more for AI” to “pay more for conversational language learning” that the new subscription tier really took off.
Duolingo requires all PMs to be daily users of its app, and the company A/B tests every product change. This has led to a world-class product development culture built on both strong product intuition and rigorous experimentation.
Duolingo always starts with the user problem that needs to be solved and works backward from there. This helps avoid “technology in search of a problem,” which is especially important right now as AI is unlocking all sorts of new technology.
Duolingo is also encouraging its PMs to invest in AI tools to boost efficiency. This includes using tools like Replit to build prototypes without engineers, and building internal tools to predict the impact of an A/B test based on previous experiments.

Natalia Castillejo: