Open source privacy and security focused mobile OS with Android app compatibility.
OEM support for the device is needed because an alternate OS cannot provide firmware updates otherwise. In practice, driver updates also come from the OEM. Providing the Android Open Source Project backports is nowhere close to full security patches. It’s unfortunate that most alternate operating systems mislead users about this by setting an inaccurate Android security patch level field, not being honest about what’s missing and downplaying the importance of it.
GmsCompatConfig is the text-based configuration for the GrapheneOS sandboxed Google Play compatibility layer. It provides a large portion of the compatibility shims and sets the maximum supported versions for Play services and the Play Store.