FusionAuth - FusionAuth is a CIAM platform that is 100% free for unlimited users.
Keybase Chat - End-to-end encrypted chat built into Keybase
GrapheneOS - GrapheneOS is an open source privacy and security focused mobile OS with Android app compatibility.
Cyph - Cyph is the name of a completely free chatting website that provides its visitors with a secure and safe chatting environment.
blockslack.io - Chat for small teams — encrypted and decentralized
Chadder - Encrypted messaging app