Oh and the i2c etc stuff, I connected ESP32 and other microcontrollers over USB.

I have an old pentium laptop N3520 with 4GB DDR3. I removed everything and put it in a receiver box 1U size. It consumes so little energy that it can run 5-7 hours from its battery (I call it build in USV). Last time I measured 3-7w. Also passiv cooled , no noise. Another machine I use , is with a i7 4770 with 16GB for Proxmox, 7-20w , peak is much higher but rarely used , only on boot and vm startup.

SailfishOS also supports Sony Xperia 10 devices

The GrapheneOS dev is looking into that. We can just wait and see. Or help if we have the skillset

https://bsky.app/profile/grapheneos.org/post/3lrekg74mjc22

Because Android AOSP gets cutting down by Google. They remove more features year by year and make them proprietary.

Is there even one Mobile OS with full functionality that is 100% FOSS? Functionality implies NFC and Banking DRM Content watching Third party app install Phone Calls The default functionalities.

True. The entire OS is not FOSS https://docs.sailfishos.org/Services/Development/Sailfish_OS_Source/

SailfishOS

SailfishOS can do that. They have a sandbox for android that you should not really notice as a end user.

SailfishOS (on Sony Xperia 10) and UbuntuTouch exist. Also the PinePhone but that is low low end.

And here I am