Clarify Auditor's supported devices (#2123)

docs/android.md

@@ -225,7 +225,7 @@ We recommend a wide variety of Android apps throughout this site. The apps liste
     ![Auditor logo](assets/img/android/auditor.svg#only-light){ align=right }
     ![Auditor logo](assets/img/android/auditor-dark.svg#only-dark){ align=right }
 
-    **Auditor** is an app which leverages hardware security features to provide device integrity monitoring for [supported devices](https://attestation.app/about#device-support). Currently, it only works with GrapheneOS and the device's stock operating system.
+    **Auditor** is an app which leverages hardware security features to provide device integrity monitoring by actively validating the identity of a device and the integrity of its operating system. Currently, it only works with GrapheneOS or the stock operating system for [supported devices](https://attestation.app/about#device-support).
 
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