Almost all those can be self-hosted, and built from source, so matrix, xmpp, simplex, are fine. Don't use anything that's uses a centralized server in a five eyes country, like signal or threema.

Snikket is an attempt to solve the XMPP issues, or at least to reduce them, single all-in-one XMPP server distro and clients across platforms, and since it's self-hosted no one should get their hands on your data (in normal circumstances).

That said, the saying goes "Perfect is the enemy of Good". Just because a solution is not perfect doesn't make it unusable, any of those options you mention full of problems are a helluva better than FB Messenger or plain SMS for example. Depending on your threat model they might be more than enough.

So, we have reasons not to use Signal, reasons not to use Matrix

yes, nearly all possible things in the world have been argued by someone somewhere already

Depends a lot on who you're talking to, and your, and their threat models. For many, signal provides pretty good protection, which brings us to a salient point, anything that actually provides good security will attract plenty of negativity, often from state level actors who feel (are) threatened. If you're playing at that level, adam_y is right, dead drops and one time pads. Presuming lesser threat, signal beats telegram and FB etc. Email is plaintext unless proton to proton, encrypted email is fine (look at PGP) and indeed if you encrypt at home before sending it's pretty much a dead drop anyway, as long as the other party has a key, and I'm wandering off the beaten path.

Seems you want a secure messenger that works and are scared by random crap because you don't have the relevant knowledge to decide (spoiler, very few do, and it's insider knowledge, the world is imperfect), fair enough, but don't let perfect be the enemy of good. As long as you're willing to give up your phone number, Signal is well regarded (exchange privacy for security, you decide). But yeah, no perfects, world imperfect, trust hard, deal ;)

XMPP lacks good clients and suffers from fragmentation of protocol standards implementation

• For Android: Conversations is excellent, also on F-Droid if you don't want to use the Google store.
• For iOS/MacOS: Siskin or iOS/MacOS: Monal.
• For Linux/Windows: Gajim or Linux: Dino.

"Protocol fragmentation" is not a valid complaint about XMPP -- it's like complaining that ActivityPub is fragmented; but that's not a problem: you use the services (Mastodon, Lemmy, Kbin, etc) built with it which suit your needs, mostly interacting with that sector of the federation (eg, Lemmy+Kbin), but get a little interoperability with other sectors as a bonus (eg, Lemmy+Mastodon).

I don't consider those comments regarding Matrix as problematic. Don't use someone else's server if you don't trust them - including a third party lookup server.

/selfhosting Matrix

People say this over and over "depends on your threat model" and yet people seem to have a hard time understanding that. Your threat model is "who is your adversary and what he is willing/able to do". Your security goal is what do you want to keep from your adversary.

As others said, if you are an activist or sth important, perhaps you might want to build a working knowledge of cryptography yourself. If you just want META not being able to see your NSFW chat with your romantic partner Signal might be more than enough. In fact, people way more relevant than me also suggest that Signal is good even for bounty hunter vulnerability reporting.

Having said that, what bugs me most is that people think the instant messaging format as suitable for everything: activism, jobs, crimes, broadcasting 1970's prog rock for extraterestrials , whatever lmao. Do you really want to use your phone for all that? Like, just carrying the phone around in the first place nullifies your other precautions, for all advanced threat models beyond privacy of non-critical social messaging.

Persistent/resourceful adversaries can eventually get to you, using a set of penetration and intelligence techniques, which means, if you are involved, the convenience of messaging your partners in crime from the phone in your pocket while waiting for a bus is a convenience you probably can't afford.

Use Signal or Simplex.

Signal does require a phone number. However, as long as you understand what that means you are fine.

It really just depends on your threat model.

Think it in this way: What is the most secure way to walk in the city? You'll need a team of armed bodyguards and wear a full bulletproof vest. Do you REALLY need this level of security? Who are you protecting from? If the answer is a criminal organization or law enforcement, then yes, probably. But if the answer is a random thief, then you'll probably need to just carry a gun, pepper spray, knife etc.

Same goes for privacy online and messenger in this case. Are you an activist or a drug dealer? Then you'll probably need Tails + something like SimpleX via TOR. Otherwise, if you are just concerned of typical surveillance capitalism (and don't want the government to scan your chats like it probably will in the EU after Chat Control), in my opinion, Signal is the best compromise of privacy, security and convenience.

You will always find problems associated with every thing but here's some recommandations :

For a good start, Signal and his forks (molly...)

For daily basis and better than Signal, choose SimpleX (SimpleX is only feature incomplete for the mainstream app, but in it you can send texts, voices, photos, videos, live messages, have a PP, a alias for your contacts...)

Important stuff and activism, use Briar

There are a few that do a good job of protecting our messages with end-to-end encryption, but no single one fits all use cases beyond that, so we have to prioritize our needs.

Signal is pretty okayish at meta-data protection (at the application level), but has a single point of failure/monitoring, requires linking a phone number to your account, can't be self-hosted in any useful way, and is (practically speaking) bound to services run by privacy invaders like Google.

Matrix is decentralized, self-hostable, anonymous, and has good multi-device support, but hasn't yet moved certain meta-data into the encrypted channel.

SimpleX makes it relatively easy to avoid revealing a single user ID to multiple contacts (queue IDs are user IDs despite the misleading marketing) and plans to implement multi-hop routing to protect meta-data better than Signal can (is this implemented yet?), but lacks multi-device support, lacks group calls, drops messages if they're not retrieved within 3 weeks, and has an unclear future because it depends on venture capital to operate and to continue development.

I use Matrix because it has the features that I and my contacts expect, and can route around system failures, attacks, and government interference. This means it will still operate even if political and financial landscapes change, so I can count on at least some of my social network remaining intact for a long time to come, rather than having to ask everyone to adopt a new messenger again at some point. For my use case, these things are more important than hiding which accounts are talking to each other, so it's a tradeoff that makes sense for me. (Also, Matrix has acknowledged the meta-data problem and indicated that they want to fix it eventually.)

Some people have different use cases, though. Notably, whistleblowers and journalists whose safety depends on hiding who they're talking to should prioritize meta-data protection over things like multi-device support and long-term network resilience, and should avoid linking identifying info like a phone number to their account.

jami has so much potential. just wish it ran a bit more reliable

I'm using simplex without problems. I get all notifications and didn't notice an increased battery drain.

Wire is the best for security (it literally won't let you send messages unencrypted), cost (its free), privacy (no phone number required), and usability for the masses (Foss client on all the platforms, messages sync between each client like you'd expect)

I haven't found anything that checks all those boxes other than Wire (though I do wish we had other options that came close)

https://Wire.com

Conversations?

XMPP clients are fine albeit it all, as many as they are, slightly different as is the nature of the protocol. This just means there is value in contributing to existing clients, creating new clients, or embracing progressive enhancement (which most do for example with emoji reactions just being a quoted text reply & so on) & complete feature parity is a fool’s errand if you want an exensible protocol with diversity & experimentation in the community. With the broad exception of the Conversations Compliance, there isn’t a flagship client & instead the best ideas come to the most used or most innovative clients. I use Cheogram, Profanity, Gajim, Dino, Movim at different times (& would love to create my own). The protocol is stable, healthy, & ready for proposals for improvement.

If I compare this to the more-expensive-by-all-metrics-to-run Matrix, if it ain’t Element, you gotta problem since a vast majority of users are on it & using all of its features & no other client has anything near parity but are expected to have parity instead of allowing things to sometimes be gracefully missed or shown in a less than ideal manner as acceptable. This hurts experimentation. Good luck trying anything similar to GDPR when all nodes are design & required to duplicate all messages & attachments for all users to every server anyone in it comes from.

The only real gotcha is the same gotcha as Matrix when using multiple clients with double-ratchet encryption (ala Signal) is that clients will expire keys that haven’t been seen in a while & is hard to get both devices retrusting one another. Turning it off & on again rarely works & requires fiddling on both ends sometimes. I really should just use PGP for encryption more often…

You could try Molly if you don't like Signal

The SimpleX battery drain issue does not affect everyone. At least for me, it has been perfectly fine.

@JustMarkov "Good" by what standard?
How anonymous do you really need to be? How much convenience are you willing to sacrifice in the name of secrecy?
I'm not an activist or journalist, I don't live in a very authoritarian country (although I'm a bit cautious about sharing my political views)
So, for me sharing a phone number is not a big deal. But for others it might mean more.

good messenger for what?

if you want a solution for you and a bunch of your henchmen to coordinate and discuss totally-not-crimes with ephemeral comms, practically any E2EE solution will work; once the not-crimen is done, burn your accounts and toss the devices for good measure and you're scot free.

if you want a secure messenger that's part of a widely used communication platform where you can also do normal people shit and also convert normal people to actually use it (think getting contact deets from cute boy/girl at a bar or giving yours to a business correspondent without an elaborate powerpoint presentation on how to use it) and you want to enjoy the fruits of 20+ years of continuous IM development, like having top-notch UX, battery efficiency, network resiliency, quality voice/video calls, etc., without being spied on then such a thing doesn't exist.

how come? meredith baxter recently stated that it costs signal $50MM/yr to run their infra. that money has to come from somewhere. if there are no advertising dolts dumping cash on spying on your social graph and convos, the remaining avenues for financing are few and far between.

in closing, there aren't any super awesome messengers you weren't aware of, everything is shit.

Signal, Threema, SimpleX.

Your source is ridiculous. Please educate yourself about more how Signal works.

Kind of limited due to there not being an iOS version, but Briar is pretty decent. It was made to be usable in repressive areas by press and other groups, as well as in areas where bad weather has taken out cell and regular wifi. Can be used with phone data, but also offline via ad-hoc wifi and bluetooth. But stuff like Signal and SimpleX are more overall useful to more people (and I think SimpleX also supports offline local immediate area of each other like wifi and bluetooth but I don't remember atm).

DeltaChat. I don't use it myself because it's built on electron (which basically excludes 99% of modern chat clients); but as it's technically an email client turned into a chat client, we can assume you're protected by PGP when writing to most users, and with the added effect of not needing to convince anyone to install anything since from their end it's just an email.

Just out of curiosity: why is nobody recommending Tox?

If you really need it to be secure and private, and are communicating mostly with known acquaintances within a reasonable radius, with low bandwidth requirements, LoRA with encryption is the best bet.

It is a higher bar of entry but at least you can be confident your messages won't be intercepted in any useful form.

The German technology blog Kuketz has a comprehensive overview and comparison of all major messenger services.