A free app for Android, by GrapheneOS.

What is Auditor?

Auditor is a tool that can be used to verify the integrity of an Android device. It works by receiving information from the device’s hardware security module (HSM) or trusted execution environment (TEE). The information that is received includes the device’s bootloader status, its hardware platform, and information about the device’s operating system.

After receiving this information, the app will check that the device is running the stock operating system with the bootloader locked. It will also check that no tampering has occurred with the operating system.

If the device is not running the stock operating system, or if there is a risk of the device being used with malware, the app will notify the user of the risk.