In a way, Discord is to Matrix as Reddit is to Lemmy. Where Discord/Reddit are centrally hosted by the company that owns them (meaning they set the rules, their downtime is your downtime, etc.), Matrix/Lemmy are federated platforms mostly hosted by other users. If you understand Lemmy, you get the basic idea of Matrix, except that it’s meant for live chat instead of threaded forum discussions.

Something people get stuck on about Discord is the expression “Discord server”, in the sense of “Join my Discord server.” This is technically not accurate: Discord servers are more like subreddits are on Reddit, in that Discord is actually hosting all of them and to some degree in charge of them. They’re not servers in the Lemmy/Matrix sense, as in “the place where you come from”, like lemm.ee or lemmy.world are, they’re more like individual communities.

The equivalent of this on Matrix (i.e. a Discord “server”/Reddit subreddit/Lemmy community) is called a space. From there, the analogy follows in a pretty straightforward way. You sign up with a homeserver and join whatever Matrix spaces (“Discord servers”) are interesting to you. Like Discord, you can either use Matrix from your web browser or download an app–unlike Discord, there’s tons of apps instead of just the one official one.

That’s the concept. It works pretty well, sometimes. I’ve been using it daily for about four years, and when using a PC, it’s pretty good. There’s several fairly mature web/desktop apps, including the quasi-official one, Element. The problems start when you look to use Matrix from Android/iOS. All of the mobile apps offer a heavily degraded experience compared to desktop or even competing platforms like Discord–and that’s including the fact that the official Discord app is awful.

None of the mobile apps are in a complete or stable enough condition to be sensible replacements for Discord unless you heavily temper your expectations. If you want to use Matrix on your phone–and it’s 2025, so you probably do–you basically have to be ideologically invested in Matrix to make it your primary live chat platform. If you can deal with the problems because you believe in the ideals of decentralization and end-to-end encryption, then Matrix is workable.