GrapheneOS, the pinnacle of mobile phone freedom that only works on Google devices.
Discussion
Bring back Cyanogenmod.
The argument against supporting other devices always seems to be because of the Google Titan secure chip. Kinda surprised GrapheneOS hasn't been forked to support more hardware and an app like Obtainium as the "App Store".
I'd love it if I could buy pieces of a phone and snap it together and mix and match parts, upgrade a piece at a time. Customizable hardware, might be a future big thing