Most instant messenger apps, like WhatsApp, violate your privacy. We'll recommend encrypted privacy-respecting messengers.
Session keeps your communication private, secure, and anonymous. When using Session, your messages are sent to their destinations through a decentralized "onion routing" network similar to Tor, using a system called onion requests.
Today, Element is a modern privacy-friendly alternative to Discord, IRC, and Microsoft Teams. Like Session, Matrix utilizes end-to-end encryption by default, and is very secure, but Session is a more private and secure alternative.