Messenger Video Calls - Facebook Messenger, now with HD video calls
Polymail - Native email app for email productivity.
Slack Video Messaging by Standuply - Easily record and send video messages in Slack 📹
Airmail - Airmail is a lightweight and lightning fast mail client for Mac.
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.
Spark Mail - Spark helps you take your inbox under control. Instantly see what’s important and quickly clean up the rest. Spark for Teams allows you to create, discuss, and share email with your colleagues