Signal: The Best Secure Communication App
The Signal App is one of the best encrypted app for secure communication. Signal can be used for audio, video, and texting. There can be group and individual calls. To date, governments are not able to break the encryption.
It is a free, open source software that doesn't track you. You can set messages to disappear.
Switch from What'sApp and other apps to Signal. Great connections. Still does not replace a Satellite phone, and I advocate for redundancy when affordability.
You may want to use WhatsApp for unimportant communication that is okay for the government or police to listen in and read, so that you are predictable to them and so it does not look like you are hiding anything. But use Signal for everything else.
To learn how to use Signal, check Youtube for help videos.
(I'm not paid for this post.)