"If it's not an official OS, we have to assume it's bad."
That's how Shawn Wilden, the tech lead for hardware-backed security in Android, described the current reality of custom Android-based operating systems in response to a real security conundrum. GrapheneOS users discovered recently that Authy, a popular (and generally well-regarded) two-factor authentication manager, will not work on their phones—phones running an OS intended to be more secure and hardened than any standard Android phone.
"We don't want to punish users of alternative OSes, but there's really no other option at the moment," Wilden added before his blunt conclusion. "Play Integrity has absolutely no way to guess whether a given custom OS completely subverts the Android security model."