LineageOS is great, but I doubt it supports many $20 phones. Porting is done by volunteers - people who buy cheap phones are unlikely to make the effort. Also,

LineageOS is great, but I doubt it supports many $20 phones. Porting is done by volunteers - people who buy cheap phones are unlikely to make the effort. Also, in theory a rootkit could go into the embedded firmware or use a closed source kernel module. In fairness, that's not a big threat yet - cheap devices tend to get cheap rootkits...