This app use SafetyNet for attestation which require google-play-services, which is not installed on some devices/OS (such as running grapheneos, linageos, etc..)
GrapheneOS use the app Auditor: (which can be used on some other OS as well, stock or other which are properly signed, etc..)
https://github.com/GrapheneOS/Auditor
consider integrating with it as other attestation provider.
This app use SafetyNet for attestation which require google-play-services, which is not installed on some devices/OS (such as running grapheneos, linageos, etc..)
GrapheneOS use the app Auditor: (which can be used on some other OS as well, stock or other which are properly signed, etc..)
https://github.com/GrapheneOS/Auditor
consider integrating with it as other attestation provider.