Apps Related to On-premises software

Jitsi is a free and open-source suite of secure, flexible communication tools. It offers multi-platform support for voice (VoIP), video conferencing, and instant messaging, emphasizing privacy and ease of use with no account required to start a meeting.

Let's Chat is a self-hosted, open-source messaging application built for small to medium-sized teams. It provides persistent chat rooms, private messaging, and collaboration tools, prioritizing ease of deployment and control over your data.