LAN Messenger - LAN Messenger is a decentralized UDP IM-style chat client which supports usernames...
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.
Softros LAN messenger - LAN messenger for an internal office chat for home or business users. It does not require a server and is very easy to install and use. It supports personal chats, group chats, message brodcasting, files transfer and remote desktop access.
Telegram - Telegram is a messaging app with a focus on speed and security. It’s superfast, simple and free.
RealPopup.it - A network messaging application that's feature-rich yet easy-to-use and won't cost you a fortune, RealPopup LAN chat offers fast, stable messaging across your local network. No application server required, just install on your PC and start messaging!
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.