Internally, Google Wallet uses an API available on Android called Identity Credential to handle ISO 18013-5 compliant mobile driver’s licenses. This API was introduced in Android 11. In the same release, Google also introduced an enhanced version of its API, essentially leveraging the device’s secure hardware to store mobile driver’s licenses more securely. It’s called the Identity Credential HAL, and very few devices support it (and Google wanted to extend support by introducing a new requirement in Android 13 that I mentioned in my post. rice field).
However, hardware support for identity credentials is not required to support digital driver’s licenses. For older devices or devices without hardware support, Google provides a backward compatible version of the Identity Credential API. It is compatible with Android 8.0 and higher and uses another API called Android Keystore to store mobile driver licenses on the device. Keystore uses the device’s Trusted Execution Environment. This is something that Android devices have long had to support.