[voltagex_]

Hey, the replies here about CopperheadOS are pretty good for info on this.

It's a tradeoff - new phones are more secure, but they're also secured against you, e.g. if I OEM unlock my Galaxy Note 9, a bit is set permemnantly that could be used to determine whether the phone gets a warranty repair.

To get back on track, you may want to have a look to see if the "board support package" is still supported. You're well out of vendor support and it looks like the last commit to https://github.com/LineageOS/android_kernel_samsung_smdk4210... was 2013.

The gold standard would be a phone that runs a very-close or actually mainline Linux kernel, but I don't think we're there yet.

Nexus devices were fantastic, but they're gone now. Pixel, I guess, but I was scared off after the 5X and 6P hardware issues.