LetsJab

Lets Jab is based on the free and open source Rocket.Chat.

Rocket.Chat is a free and open source team chat collaboration platform that allows users to communicate securely in real-time across devices on web, desktop or mobile and to customize their interface with a range of plugins, themes and integrations with other key software.

By opting for Rocket.Chat, users also benefit from free audio and video conferencing, guest access, screen and file sharing, LiveChat, LDAP Group Sync, two-factor authentication (2FA), E2E encryption, SSO, dozens of OAuth providers and unlimited users, guests, channels, messages, searches and files. Users can set up Rocket.Chat on cloud or by hosting their own servers on-premises. Thats where LetsJab Comes in!

With more than 700 developer-contributors and over 17k stars on Github, Rocket.Chat has the largest and most active community of chat developers in the open source communication sector.