Riot : Riot allows teams to communicate across a wide range of collaboration apps. If some team members use Riot while others use IRC, Slack or Gitter, Riot ...
Zulip : Powerful slack-like open source group chat
Rocket.Chat : Rocket.Chat is a Web Chat Server, developed in JavaScript, using the Meteor fullstack framework.
It is a great solution for communities and companies ...
Gallery : Open source web based photo album organizer. Gallery gives you an intuitive way to blend photo management seamlessly into your own website whether you...
OpenPhoto : A free, hosted, portable and open source photo sharing service. A photo application that lets you store your photos on Dropbox, Amazon S3 or in your g...
Mattermost is a self-hosted solution for bringing all your team communication to one place, and making it searchable and accessible anywhere