[unethical_ban]

It's unfortunate that Briar is android-only. I know it is due to Apple restrictions on battery usage (afaik). But it is decentralized and can operate locally over wifi and Bluetooth.

These seem like good practical steps.

GrapheneOS has duress pins (type it in, and the phone is wiped). It has secondary pins for biometric - the intent being that your real password is a long passphrase, and "quick " unlock is bio+pin.

I would add to this list some method of uploading video live to another service, in a way that the video can't be deleted via the phone. I know those exist for the express purpose of civil rights, I think the aclu has a list somewhere.