The web-based messaging service Rocket.Chat focuses on communication within groups or teams. If you use Rocket Chat you can provide your team members with a user account and then use this account to communicate easily with each other in public or private groups.
Rocket.Chat is used via the browser. But it is also available as an app on your own device. The chat supports the sending of files, pictures and videos as well as the integration of other services, such as a connection to the ticket system Redmine. We enable the application on an own server or offer the service in our Cloud Service.
If you are looking for a privacy friendly video conferencing platform running on your own server, the open source tool Jitsi is the right choice. Jitsi is an alternative to Zoom. It does not store user data and allows the encrypted application.
If you are uncomfortable with video conferencing in the cloud of a company based in the USA, because you have to make sure that no recordings are made or data is collected by unauthorized third parties, then you should decide to use Jitsi InHouse.
Jitsi is then as secure as you want it to be. And the handling for the user is as easy as possible. It is enough to call a URL in the browser. And a registration of your users for an online meeting is no longer necessary.