Update README.md

README.md

@@ -1,23 +1,11 @@
 Android Key Attestation Sample App
 ==============================
 
-This sample illustrates how to use the [Bouncy Castle ASN.1][1] parser to extract information
-from an Android attestation data structure to verify that a key pair has been
-generated in an Android device. This sample demonstrates how to generate and verify a certificate on a device.
+This app supports generating, saving, loading, parsing and verifying Android [key and ID attestation](https://source.android.com/docs/security/features/keystore/attestation) data.
 
-[1]: https://www.bouncycastle.org/
-
-
-Note that this sample demonstrates the verification of a certificate on the Android framework and not
-on a server. Although can test the certificate and extensions directly
-on a device, it is safer to run these checks on a separate server you can trust.
-
-Getting Started
----------------
-
-This sample uses the Gradle build system. To build this project, use the
-`gradlew aR` command or use "Open Project" in Android Studio.
+The app is used for self-testing, so it has no network permission. The certificate revocation data is embedded in the apk and will not be updated online. If the system is compromised, parsing and verifying is not safe, you should save the data to a file and then load the file on another device to verify it.
 
+This app also supports parsing attestation data generated by other software, and the supported storage format is [PkiPath](https://docs.oracle.com/en/java/javase/17/docs/specs/security/standard-names.html#certpath-encodings).
 
 License
 -------