Dmail - Dmail makes it safe&private for you to communicate storage and transfer tokens&NFT's on Dfinity

Spike - Spike solves businesses' communication chaos by bringing together email, team chat, collaborative docs, and meetings, into one feed.

Ugly Email for FireFox - Get back your email privacy, block email tracking

Keybase Chat - End-to-end encrypted chat built into Keybase

FastMail - Email, calendars, and contacts to highest standards of security, privacy and reliability.

Crypho - End-to-end-encrypted messaging and file sharing