2 phones. One is used only for hostspot. Second is used only in wifi mode. You take a sim card that you can obtain without id. Register signal, whatsapp, whatev

2 phones. One is used only for hostspot. Second is used only in wifi mode. You take a sim card that you can obtain without id. Register signal, whatsapp, whatever with pin on the second phone. Use threema. Second phone should be rooted with very strict firewall. That should make someone sweat if they want to get in the endpoint.