Messenger (Facebook) : very widespread, messages exchanged via Messenger are not secured by default. You have to use the
secret conversation option in order to have an end-to-end encrypted conversation. This means that only you and the person you are talking to have the keys to decrypt the audio or text messages you exchange. These are encrypted on your smartphone and then decrypted on the smartphone of the person you are communicating with.“>end-to-end encrypted conversation</tooltip>