Even if you’re using a privacy-focused app like Signal, if your messages are shown in notifications (which is the default), Apple will give up your messages with a subpoena. You can turn off showing the message contents in notifications, which you’ll need to do and then convince all your friends to do as well if you want messages to be truly private

Is this true? I.e. Apple can ship notification contents after an app has made the actual notifications with contents? Can’t read the linked article behind the paywall

What have you heard re Samsung?

Which oem and why?

One of the signal Devs has said they’ve already tested restoring cross platform with this new format

This new backup format is incremental and they will bring this new format to local backups in the future

Their privacy policy is good