i can&#x27;t say much for telegram as their encryption has been broken, and is not an openned, but whatsapp&#x27;s new signal protocol designed by moxy marlinspike doesn&#x27;t use sms to authenticate. It doesn&#x27;t by default require authentication, but rather has it as an option and the option generates a long 80 character passcode or QR code, to be communicated in person or via some out of band communication channel, similar to threma. Maybe they are talking about old whatsapp?