Signal

Signal is an encrypted messaging service for instant messaging, voice, and video calls and the functions include sending text, voice notes, images, videos, and files.

Signal is at the moment considered the most private video call and messaging app in the world, but this comes only after Session.

You will still need a phone number to get Signal and this could trace you and someone might be able to figure out who are you sending messages to.

Although no one can read your messages not even the Signal owners still if you send fucked up shit they might come back at you.

Signal allows you to call in an encrypted way, and send private messages to form mobile and PC apps, and it is free to use.