Android App Links
Android App Links are https deep links verified against your domain, so tapping one opens your app directly instead of the browser or an app chooser.
Your app declares the domain in an intent filter with autoVerify, and the domain serves a Digital Asset Links file, assetlinks.json, listing your package name and the SHA-256 fingerprint of every key your app is signed with. Android verifies the pairing and keeps the result.
The most common failure is a missing fingerprint — usually the Play App Signing key, since Google re-signs store builds with its own key. On Android 12 and later, adb shell pm get-app-links shows whether the device verified your domain.