I'm using https://lineageos.org/ https://lineageos.org/ (previously known as CyanogenMod) on most of my older Devices. I think this is as close to an open sourc

I'm using https://lineageos.org/ https://lineageos.org/ (previously known as CyanogenMod) on most of my older Devices. I think this is as close to an open source OS as you can get right now.