Openfire - Openfire (formerly Wildfire) is a cross-platform instant messaging (IM) and groupchat server.
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.
Bopup Communication Server - Secure instant messaging (IM) and private LAN chat solutions for organizing effective real-time communication system over office LANs, business and corporate large networks, or enterprise-size WANs and VPNs
Telegram - Telegram is a messaging app with a focus on speed and security. It’s superfast, simple and free.
ejabberd SaaS - Realtime XMPP and MQTT Software and Infrastructure as a Service.
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.