Mailspring - Mailspring is a mail client for Mac, Windows and Linux.
Zoom - Equip your team with tools designed to collaborate, connect, and engage with teammates and customers, no matter where you’re located, all in one platform.
Geary - Geary is an email application built for GNOME 3.
Telegram - Telegram is a messaging app with a focus on speed and security. It’s superfast, simple and free.
The Bat - The Bat! is a secure desktop email client for Windows, designed to protect your correspondence against third-parties and to save your time.
WhatsApp - WhatsApp Messenger: More than 1 billion people in over 180 countries use WhatsApp to stay in touch with friends and family, anytime and anywhere.