Heads up to all #Riot users: with the recent attack on @matrix' infrastructure, it's possible that Riot's Google Play version got compromised. This doesn't affect Riot's F-Droid version. Just as Riot started to do now, F-Droid has always signed all its apps on an inaccessible, offline machine. For more information, see https://riot.im/reinstall
To avoid maintenance overhead, however, it's likely to happen that F-Droid users must also change the app in near future. Still, there's no need to act now.
Matrix' biggest feature is its bridging to Telegram, Discord, several IRC networks, Slack, and possibly others (nice for using Freenode over Tor, in particular). It's sort of analogous to irccloud-like bouncing services, except more generalized. It's essentially just http and json, so it's useful for blogging, image and file galleries, pastebins, and a lot of other things just waiting to be thought of.
Server run by the main developers of the project It is not focused on any particular niche interest - everyone is welcome as long as you follow our code of conduct!