This developer tutorial covers two unique builds. The first is WebAuthn for websites and building upon that is a FIDO2 build for Android. This presentation is based on two interactive code labs from Google.
The web portion covers how to build a website with a simple re-authentication functionality using a fingerprint sensor. Re-authentication is a concept where a user signs into a website once, then authenticate again as they try to enter important sections of the website, or come back after a certain interval, etc in order to protect the account. (Your First WebAuthn Codelab via Google)
The Android portion covers how to build an Android app with a simple re-authentication functionality using fingerprint sensor. (Your First Android FIDO2 API Codelab via Google)
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