# private messengers compared: matrix, signal, session, threema, briar, simplex (and yes, whatsapp)

People ask me sometimes why I bother with Matrix when Signal exists. Fair question. There’s a lot of “private” messengers out there and honestly they are all trying to solve slightly different problems. So here’s my take on the ones I actually have opinions about.

Quick disclaimer: I run a Matrix server, so of course I’m biased. I’ll try to be fair anyway.

Signal

Signal is the default answer, and for good reason. The encryption is basically the gold standard, the apps are polished, and it’s easy enough that you can get your parents on it. If someone asks me “what should I use instead of WhatsApp” and they don’t want a lecture, I say Signal.

But it has two problems that bother me. First, it wants your phone number. They added usernames a while ago, so you can hide it from other people, but Signal itself still knows who you are. Second, it’s one centralized service run by one foundation in one country. If Signal goes down, or gets blocked, or makes a decision you don’t like, there is no plan B. You can’t take your account somewhere else. That’s the exact thing I wrote about in my first post.

And this is not theoretical anymore. Signal has been fighting laws in the UK for years, and just recently they threatened to pull out of Canada over a proposed law there. They also said they need something like 50 million dollars a year to keep running. I trust them to fight the good fight, but the point stands: when everything depends on one organization, their problems become your problems.

Matrix

You knew this was coming. Matrix is not an app, it’s a network. Nobody owns it, anyone can run a server (hi), and servers talk to each other like email does. End-to-end encryption is on by default in private chats.

It’s also been a good year for Matrix, honestly. Matrix 2.0 and the new Element X client fixed a lot of the old sluggishness, governments in Europe keep adopting it for their internal comms (France and Germany run huge deployments), and when Discord announced their age verification thing in February, a nice wave of people came looking for alternatives and found Matrix. And that makes sense, because for communities, public rooms, spaces, that whole Discord-shaped use case, Matrix is currently simply the best option on this list. Nothing else here even really tries: Signal groups are private only, and you’ll see later what I think about big groups on SimpleX.

The honest downsides: the experience depends a lot on which client and server you use, encryption in huge public rooms can still be a bit clunky, and metadata (who talks to who, room names, that kind of stuff) is more visible to servers than on Signal. Also the Matrix Foundation itself is chronically underfunded, they say reaching break-even is the goal for this year. The protocol won’t disappear if they struggle, it’s open and the code is everywhere, but it’s a reminder that open infrastructure runs on too little money.

And since I’m being honest, there’s one thing that bothers me as a server admin: how much of Matrix is effectively one company, Element. They employ most of the core developers, they make the flagship clients, and they make Synapse, the server implementation almost everyone runs (including me). In 2023 they relicensed Synapse from Apache to AGPL, with a contributor agreement that lets Element alone sell commercial licenses on top of everyone’s contributions. AGPL is a fine license, but the move made it clear who holds the steering wheel. It’s an open network on paper, and it really is, I can leave any time with the protocol intact. But in practice the health of the ecosystem depends a lot on one company’s business surviving, and I’d sleep better if the server side was more diverse.

Anyway, Matrix still trades some tightness for something I think matters more long term: you’re not renting your identity from a single company. Worst case your server dies, you make an account elsewhere and keep going.

So: Signal is a better product, Matrix is a better network. Pick what you’re optimizing for.

Threema

Threema is interesting because it’s the “pay once, no phone number” option. It’s Swiss, it’s been around forever, and you get a random ID instead of giving your number. The apps are decent and the company had a reasonable track record.

Had, past tense, because I have to be honest here: the original founders left the company back in 2024, and this January a German private equity firm announced they’re acquiring Threema. Maybe nothing changes. But “privacy company gets bought by private equity” is not a sentence that usually ends well, and it’s exactly the risk of trusting one company with your messenger. I’d be careful recommending it right now.

The other catch is that it costs a few euros, which sounds like nothing but is actually a real barrier when you try to move a group chat there. “Just install this app” already loses half the people, “just install this app and pay for it” loses the rest. And it’s still centralized, same story as Signal, just with a different flag on it.

Session

Session took the Signal protocol idea and removed the phone number and the central server. Your messages get routed through a decentralized node network, so in theory nobody can see who is talking to who. No identifier needed at all, you just get a key.

I want to like Session more than I do. The anonymity story is genuinely strong. But they changed the encryption in ways cryptographers were not happy about (they dropped forward secrecy, which means one leaked key can expose your past messages), and the whole thing is tied to a crypto token ecosystem which always makes me a bit nervous.

The project also had a rough time lately. It started in Australia, and after Australian police literally showed up at an employee’s home, the foundation moved to Switzerland in 2024. Then earlier this year they announced they were 90 days from shutting down completely because the money ran out. Donations saved it at the last minute (a big chunk came from Vitalik Buterin, of all people), but it’s running on a skeleton crew now. Funny enough, the day this post goes up was supposed to be the shutdown date. I’m glad it survived, but it shows the risk of these smaller centralized-ish projects: your messenger can just… end. Between the weakened encryption, the token stuff and the funding drama, I honestly can’t recommend Session anymore. If you need that level of anonymity, look at SimpleX instead.

Briar

Briar is the extreme one, and I respect it a lot. No servers at all. Messages go peer to peer over Tor, and if the internet is down it can literally sync over Bluetooth or WiFi between phones that are near each other. This is the messenger you want during a protest or an internet blackout.

The cost of that design is convenience. Both people basically need to be online for messages to go through, there’s no real multi-device story, battery usage is rough, and iOS support is still not there (the team says iOS is too locked down for the background stuff P2P needs, which honestly says more about Apple than about Briar). It’s developed by a small non-profit on grant money, still getting steady updates in 2026, just slowly. Briar is not trying to replace WhatsApp, it’s a tool for situations where everything else fails. Good to have installed, not something you daily drive.

What I secretly wish existed is something in between Briar and Matrix: a federated protocol with real servers, but where the servers talk to each other over Tor or i2p. You’d keep the convenience of servers (offline delivery, multi-device, your phone not running a Tor node all day), but the network layer wouldn’t leak who federates with who. And if the entire stack ran over Tor, clients included, a lot of the metadata problems I complained about in the Matrix section would stop being such big issues: the server still sees which accounts talk to each other, but it couldn’t tie any of it to an IP address or a real identity anymore, because you’d be connecting over Tor and staying anonymous. Same between servers, so federation wouldn’t reveal anything either. As a bonus, a network like that would be very hard to block: no fixed IPs or domains to blacklist, just onion services. Remember what happened to WhatsApp in Russia, that kind of country-wide block basically stops working. Matrix over onion services sort of half-works if you force it, but nothing is built for that from the ground up. If someone knows a project like this, message me, seriously.

WhatsApp

Okay, the elephant. WhatsApp actually uses the Signal protocol for encryption, so the message content itself is protected. Credit where it’s due, that’s billions of people with end-to-end encryption who never asked for it.

The problem is everything around the messages. WhatsApp belongs to Meta, and Meta’s whole business is knowing things about you. They can’t read your texts, but they know who you talk to, when, how often, from where, and they connect all of it to the biggest advertising profile on earth. Encryption of content is not the same as privacy. WhatsApp is proof of that.

And it’s getting worse, not better. This year WhatsApp got ads, and Meta AI is now baked into the app. Anything you say to the AI is processed on Meta’s servers, outside the end-to-end encryption, and their new policy says those AI conversations feed into ad targeting, with no opt-out. So the encrypted messenger now ships with a built-in unencrypted channel straight to the ad machine. They also finally added usernames so you can hide your phone number from strangers, which is nice I guess. Oh, and Russia blocked WhatsApp entirely this year, which is a good reminder that centralized apps can vanish from a whole country overnight.

If your family is on it and won’t move, fine, at least the messages between humans are still encrypted. Just don’t talk to the AI, and don’t call it a private messenger.

SimpleX

SimpleX is the newest project on this list, and its core idea is genuinely different: there are no user identifiers at all. Not a phone number, not a username, not even a random key that ties your chats together. Every conversation runs through its own pair of one-way message queues on relay servers, and the two directions of a chat don’t even have to use the same server. From the network’s point of view, “your account” simply doesn’t exist, so there’s nothing to correlate. On paper it’s the most private design of all of these.

The relays are worth explaining because it’s a nice middle ground: SimpleX runs default servers, but they’re basically dumb mailboxes that hold encrypted queues, and you can switch to other people’s relays or self-host your own without losing anything, since your identity was never on a server to begin with. That also means contact discovery works differently: you connect by sharing a link or QR code out of band, there’s no “find friends by number” and never will be, which is a feature or a dealbreaker depending on who you ask.

It’s also picking up momentum: Trail of Bits reviewed the cryptographic design, another security assessment is planned for this summer, and the funding situation looks healthier than most (Jack Dorsey invested, and Vitalik Buterin donated to them too, apparently he’s just going around funding private messengers now). A Russian court fined them for refusing to hand over user data, and their transparency report says they had nothing to hand over anyway, which is kind of the best advertisement a private messenger can get.

The downsides are the flip side of the design. It’s young, and the UX shows it. No identifiers means moving to a new phone or adding a device is more fiddly than elsewhere. And larger groups or communities are honestly where it falls apart: a “group” is really just a pile of pairwise connections, every message gets fanned out to every member separately, so anything beyond a small friend group gets slow and unreliable. If you want Matrix-style public rooms and communities, SimpleX is simply the wrong tool.

One more thing that bugs me about the design. By default, when you talk to someone, the traffic to their queue gets proxied through your own relay servers. That’s meant to hide your IP from unknown servers, which is fair, but it means your relay is in the loop for both directions: it knows when you send a message and when you check for or receive one. That’s exactly the kind of timing metadata this whole design is supposed to avoid, just concentrated at your own relay instead. I’d much rather they shipped an in-app Tor proxy (or something like it) so you talk to every queue directly and anonymously, instead of routing your activity pattern through one server that gets to watch it all. You can run the app over Tor yourself, but defaults are what actually matter.

And the funding is venture money, which I’d keep half an eye on; investors eventually want something back. Still, of everything on this list it’s the project I’m most curious about, and it’s the one I now point people to when they ask for real anonymity, at least for one-on-one chats.

The short version

If you skipped everything above, here’s the table. Scores are out of 5, and yes it’s my personal judgement, not science:

Some of these need a footnote: Signal’s anonymity is a 2 because of the phone number, Session’s encryption a 2 for the missing forward secrecy, WhatsApp’s encryption only covers the message content, and WhatsApp’s 5/5 future is not a compliment. The reasons for everything else are up in the text.

So what should you use?

Boring answer: it depends on your threat model.

• You want easy and solid: Signal
• You want to own your identity and be part of an open network: Matrix (I know a nice server)
• You want communities and public rooms, the Discord-shaped stuff: also Matrix, nothing else comes close
• You don’t want to give any phone number and don’t mind paying: Threema, but watch how the acquisition plays out
• You need real anonymity: SimpleX (not Session, sorry)
• The internet is on fire: Briar
• Your family refuses to move: WhatsApp, I guess. I’m not mad, just disappointed.

The real point is that all of these are better than the default of doing everything through one giant ad company. Pick one, drag some friends over, and the network effect problem gets a little bit smaller for everyone.

As always, if you want to try Matrix, you know where to find me.