Only Google Pixel’s and Fairphone’s currently provide bare minimum for 3rd-party OS support: working verified boot with user-provided signing keys. None of the other phones doing that yet
Fairphone cant be supported because it does not keep up with Android updates and in particular Linux kernel updates. Currently supported Fairphone’s have EOL (outdated, not supported) Linux kernel version. They are bad in terms of other aspects like lack of MTE, lack of USB port(s) control from software level on hardware level (Pixel 6 and newer have that), etc. You cant have privacy without security
But in 2027 this may change due to Motorola and GrapheneOS partnership
There are a lot of devices with the ability to install another OS and lock the device with verified boot, but none with the required updates and security features other than Pixels. Fairphones are near the bottom for security among the available options.
It's not one of the main issues with their devices but Fairphone has had a lot of issues with verified boot including using publicly available sample private keys for signing firmware and OS images across multiple device generations. It's not a strength of their devices.
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