Because Duolingo Math isn't on the official store, developers and enthusiasts have extracted the app's APK file from test devices or cross-platform builds and hosted it on third-party websites.
⚠️ The Risks of Downloading Standalone "Duolingo Math" APKs duolingo math android apk
Duolingo is currently testing a section inside the main green owl language app for some Android users. Check your main Duolingo app: tap the barbell/skill icon. If you see Math or Music, you’re in luck. Because Duolingo Math isn't on the official store,