ProtonMail - Secure email with absolutely no compromises. Get your free encrypted email account today.
Timezone.io - Keep track where and when your team is.
GPGMail - GPGMail is an open source plugin for Apple Mail.
Spacetime - Work hour and time zone management for distributed teams.
ElectronMail - Unofficial desktop app for ProtonMail and Tutanota end-to-end encrypted email providers
Team Time Zone - Local clocks for distributed teams who use Slack