Seald - Keep your conversations secure, everywhere.
Crypho - End-to-end-encrypted messaging and file sharing
Keybase Chat - End-to-end encrypted chat built into Keybase
blockslack.io - Chat for small teams — encrypted and decentralized
Hermes - Pandora Client for OS X
aliceandbob.io - A free, light and easy to use client-side PGP tool 🔐