Duolingo

Duolingo is the world's most popular language-learning app, offering gamified lessons in over 40 languages. Their mobile engineering team has been a pioneer in adopting Kotlin Multiplatform and SwiftUI, serving over 100 million monthly active learners worldwide.

10 articles · Android, iOS, Kotlin Multiplatform

Website Tech Blog

Duolingo App Store

Duolingo Play Store

iOS Jul 10, 2025

How we used Macros to Promote MVVM architecture adoption

Kotlin Multiplatform Jul 3, 2025

Duolingo + KMP: A Case Study in Developer Productivity

Android Jun 11, 2025

Duolingo's Android Performance Case Study and DAU Growth

Android May 4, 2025

How We Slashed Android Startup Time by 30% with Baseline Profiles

iOS / Android Feb 7, 2025

How we reduced manual regression tests by 70% using AI tools

iOS / Android Dec 18, 2024

How we sped up Android and iOS builds by 68% on CI

iOS / Android Nov 8, 2024

How server-driven UI keeps our shop fresh

iOS / Android Mar 1, 2024

How dogfooding helps us build a better Duolingo

Android Aug 26, 2021

Android App Excellence: Duolingo

iOS Jan 7, 2015

Real World Swift