SimpleX Chat

SimpleX: the first network where you own your identity, contacts, and groups. Secure / decentralized / open-source. Get the app: https://simplex.chat/downloads

Security assessments:
2022: https://simplex.chat/blog/20221108-simplex-chat-v4.2-security-audit-new-website.html
2024: https://simplex.chat/blog/20241014-simplex-network-v6-1-security-review-better-calls-user-experience.html

Public Key

npub1ht6s6d0xuscv0rkt09wt7y7wzfvs6d6uk3ysf3kan44a040hh2ds5q3f5x

NIP-05 Address

simplex@mastodon-social.mostr.pub

Profile Code

nprofile1qqst4agdxhnwgvx83m9hjh9lz08pykgdxawtgjgycmwe667h6hmm4xcpz3mhxue69uhhyetvv9ujuerpd46hxtnfduqs6amnwvaz7tmwdaejumr0dsxh2vtg

Publishing to

relay.damus.io

nos.lol

Author Public Key

npub1ht6s6d0xuscv0rkt09wt7y7wzfvs6d6uk3ysf3kan44a040hh2ds5q3f5x

Show more details

Last Notes

2025-07-30 19:05:57 UTC

v6.4.1 of SimpleX Chat released!
- you can now review new members before they join ("knocking").
- new UX for connecting to other users!
- set default time to delete messages.
- app build security: Linux app builds are now reproducible (verified by our and Flux teams) and other build security improvements.
Read more: https://simplex.chat/blog/20250729-simplex-chat-v6-4-1-welcome-contacts-protect-groups-app-security.html

2025-07-10 17:05:57 UTC

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@nprofile…m8mr @nprofile…qrh4
Just to clarify, what you do or don't recommend, is entirely your business - no hard feelings here.
But not sure what you mean by "sock puppet" accounts, the implication here is that we are creating some accounts that would undermine GrapheneOS? If so, this is ridiculously untrue - all statements we make, we make under our own name.
That various people spread FUD about any system, including SimpleX network and GrapheneOS, is inevitable - whatever is their reasoning.

2025-01-15 17:43:01 UTC

Privacy-preserving content moderation - preventing abuse of SimpleX network without any compromise to users' privacy and end-to-end encryption.
https://simplex.chat/blog/20250114-simplex-network-large-groups-privacy-preserving-content-moderation.html
This is our response to #ChatControl ideas - no need to scan content to moderate it.
Post your comments!

2024-12-25 16:10:25 UTC

https://files.mastodon.social/media_attachments/files/113/714/332/722/982/201/original/13030459d6135ce7.png

2024-12-18 19:46:10 UTC

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@nprofile…0x7p how is it better than mastodon?

2024-12-18 19:45:24 UTC

Oppose digital IDs – they break the law and lead to mass scale surveillance.
The UK government plans to introduce digital IDs to prove your age in pubs.
If you are based in the UK, email your MP to voice your opposition - the post has the email draft.
https://simplex.chat/blog/20241218-oppose-digital-ids-they-break-law-lead-to-mass-scale-surveillance.html

2024-12-10 20:41:23 UTC

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@nprofile…pqg3 added Catalan to weblate

2024-12-10 19:50:31 UTC

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@nprofile…pqg3 Yes, and sorry! We're a bit drowning in everything!
Make sure to join translators group - ask our support to invite you please

2024-12-10 19:13:10 UTC

SimpleX Chat v6.2 is out!
The app now includes both servers that we operate and servers independently operated by Flux – thanks to Daniel Keller and Flux team!
More privacy and decentralization for all users!
Also in v6.2:
- business chats!
- better UX: open chat on first unread (not on iOS yet), show who reacted.
- better iOS notifications!
Read more: https://simplex.chat/blog/20241210-simplex-network-v6-2-servers-by-flux-business-chats.html

2024-11-25 21:11:08 UTC

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@nprofile…dugx @nprofile…vs97 SimpleX does provide metadata privacy. XMPP doesn't. Why should we use XMPP? It's a rather bloated spec with lots of extensions without any single client or server supporting all of them. Imagine if Web spec was like that.

2024-11-25 19:07:02 UTC

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@nprofile…qpxr XMPP has very similar problems as matrix, Matrix was just used as an example of federated messaging network.
Don't think WhatsApp uses it anymore. We believe that protocols only matter if successful products use them, and it's important to be in control of protocol to be able to build a successful product.

2024-11-25 19:02:21 UTC

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@nprofile…dugx @nprofile…vs97 we have experience with XMPP, and it doesn't provide metadata privacy, and the security of e2e encryption has many limitations. So we're building something better.
The core problem of XMPP is that it was protocol-first, and it's a dead end for any widely adopted software system - it has to be product-first.
We only have wide adoption of the Web thanks to Netscape who made it a product people can use, disregarding competing browsers.

2024-11-25 18:56:49 UTC

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@nprofile…8fy2 what problem would it solve?

2024-11-25 18:55:02 UTC

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@nprofile…qpxr we don't do xmpp, it's different protocol.

2024-11-25 14:25:47 UTC

Servers operated by Flux (https://runonflux.com) added to SimpleX Chat apps (v6.2-beta.1) to improve metadata privacy – a game changer for SimpleX network users!
https://simplex.chat/blog/20241125-servers-operated-by-flux-true-privacy-and-decentralization-for-all-users.html
Huge thanks for supporting our vision for extreme decentralization of communications!

2024-10-16 21:31:25 UTC

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@npub17f6…hyrn It is unfortunately not the case, if it were their article wouldn't merit a response. In our bubble of privacy enthusiasts we forget about a real world where 50% of people, many highly intelligent, trust mass media.
Criminal abuses on non-private platforms, and by platforms themselves (look at criminal cases alleging large platforms enabling child abuse), are under-reported, while privacy is vilified.
So shrugging it off would be wrong, it requires ongoing education and responses.

2024-10-16 18:39:56 UTC

Our criticism of recently published
Wired article: "Wired's Attack on Privacy"
https://simplex.chat/blog/20241016-wired-attack-on-privacy.html

2024-09-14 21:16:45 UTC

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@npub1sj4…2zv5 it should

2024-09-14 21:11:06 UTC

SimpleX Chat is blocked in Russia. We might have a solution next week.

2024-08-31 16:23:52 UTC

Answering your questions about private message routing in SimpleX network:
1. Does SimpleX protect IP addresses? Yes.
2. Doesn't private message routing reinvent Tor? No.
3. Why don't you embed Tor? Tor is great, but not for all.
Read more in FAQ: https://simplex.chat/faq/#does-simplex-protect-my-ip-address

2024-08-30 16:02:33 UTC

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@npub1rwr…j27u Irrespective of how it is done, changing the brand colours without consent is the violation of the designers and design owners rights.

2024-08-24 12:12:54 UTC

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Thanks to our users who highlighted these inaccuracies to us!

2024-08-24 12:12:42 UTC

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6. Is the design well documented? Somewhat
The design documentation was reviewed in preparation for design security audit - report is about to be published.

2024-08-24 12:12:27 UTC

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5. Does the company log timestamps/IP addresses? Yes
This is incorrect, we never logged IP addresses and access timestamps of the users.
Further, the private message routing that is now enabled by default for all users prevents such logging by any 3rd party servers with modified code:
https://simplex.chat/blog/20240604-simplex-chat-v5.8-private-message-routing-chat-themes.html

2024-08-24 12:12:08 UTC

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4. Directory service could be modified to enable a MITM attack? Yes
This is incorrect, as there is no user directory service, and MITM by relays is not possible by design, even without optional security code verification (that exists to mitigate MITM by the channel you used to pass one-time invitation link, e.g. email).

2024-08-24 12:11:48 UTC

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3. Cryptographic primitives: Curve25519 / XSalsa20 256 / Poly1305 (downgraded for the absence of PQ encryption).
We added PQ encryption in March this year: https://simplex.chat/blog/20240314-simplex-chat-v5-6-quantum-resistance-signal-double-ratchet-algorithm.html
This is done in the same way as Apple describes as PQ3 here: https://security.apple.com/blog/imessage-pq3/

2024-08-24 12:11:07 UTC

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2. Company jurisdiction: UK
We disagree that there are any jurisdictions that are particularly good for privacy. Also, this might be important for centralised services, like Threema, where the users can't host servers, and much less important for decentralized network, such as SimpleX, where there are hundreds (if not thousands) of servers that we don't control.

2024-08-24 12:10:24 UTC

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1. Main reasons why the app isn't recommended: Provide a transparency report
It is available online and updated at least quarterly, or if anything changes: https://simplex.chat/transparency/

2024-08-24 12:09:52 UTC

https://www.securemessagingapps.com is the great comparison of messaging apps, but there are several incorrect statements about SimpleX Chat.
Commenting in the thread below!

2024-08-20 15:15:15 UTC

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@npub1pz6…zr26 Opened now! accidentally was limited to 100 responses.

2024-08-20 15:14:54 UTC

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@npub16pp…k6jh Opened now! accidentally was limited to 100 responses.

2024-08-20 15:14:31 UTC

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@npub1f76…fr42 didn't realise that with the current settings it was limited to 100 responses! Should be open now!

2024-08-20 10:47:51 UTC

Please fill this survey about SimpleX Chat: https://gdlgeuc34xt.typeform.com/to/XAKc5N1l
It is a smaller version of the survey we did last year, please answer again if you answered then.
Thank you!

2024-08-16 09:02:06 UTC

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@npub1sd9…d4ml possibly, we will see!

2024-08-14 13:37:33 UTC

Announcing $1.3m pre-seed investment from Jack Dorsey and Asymmetric VC in SimpleX Chat🚀
https://simplex.chat/blog/20240814-simplex-chat-vision-funding-v6-private-routing-new-user-experience.html
Also SimpleX Chat v6.0 stable is now released with the new user experience and private message routing – details in the post.

2024-08-12 16:01:06 UTC

In case you missed the news, #ChatControl is back on the agenda of the EU governments.
We wrote before that strong e2e encryption is the only way to protect children online: https://simplex.chat/blog/20240601-protecting-children-safety-requires-e2e-encryption.html
Write to the MPs you voted for – every single letter can change the outcome.
https://mastodon.social/@echo_pbreyer@digitalcourage.social/112768472207989491

2024-08-11 20:18:55 UTC

Please note: we do NOT own the domain simplexchat.org - it might be a phishing site to collect the data (it has an exact copy of our website https://simplex.chat).
We submitted the complaint to the domain registrar (GNAME).
Do NOT download anything from simplexchat.org, obviously.

2024-08-08 21:41:30 UTC

SimpleX Chat v6.0-beta.4 is released!
It is stable to use, and please let us know any issues - any help testing it is really great!
You can get beta version for iOS from Apple TestFlight, and for Android from GitHub or from our F-Droid repo (it's still in review in Play Store beta channel): https://simplex.chat/downloads/
The final release will be published on 8/14, together with the announcements.
https://files.mastodon.social/media_attachments/files/112/928/573/433/865/105/original/9eadc92c396e7c7c.jpeg

2024-07-10 22:02:39 UTC

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@npub1lpz…p4e6 I don't think it would have a major difference as the app doesn't check messages, it is push. But if you do an experiment, please let me know. Using private routing should reduce battery usage a bit.

2024-06-30 18:02:36 UTC

A Q&A with the users in SimplifiedPrivacy.com group on SimpleX Chat:
https://primal.net/e/nevent1qqsxjjxykeyg7k4dm47djvu2kwzyxrctjp43ydm5s5tknrpxl2d7ltgpr4mhxue69uhkummnw3ezuenvv9kkjmn8dukk6ctfdshxxmmdqy8hwumn8ghj7efwdehhxtnvdakqzrthwden5te0dehhxtnvdakqzxrhwden5te0wfjkccte9ehx7umhdpjhyefwvdhk6q3q4slk4lshtylkrqg9z0dvng09gn58h88frvnax7uga3v0h25szj4q6gn9ha

2024-06-23 09:20:48 UTC

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@npub1m45…lyhy Yes, but isn't it the good news? Time is all we have, write more letters to representatives.

2024-06-04 19:38:13 UTC

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@npub1ule…f93v updated!

2024-06-01 20:53:49 UTC

Protecting children's safety requires privacy and end-to-end encryption:
https://simplex.chat/blog/20240601-protecting-children-safety-requires-e2e-encryption.html
Proposed "upload moderation" would fuel the very problem it aims to solve, undermining rather than protecting children's safety.
#safety #privacy #encryption

2024-05-16 19:01:25 UTC

Improving communication #privacy requires making many hard choices:
https://simplex.chat/blog/20240516-simplex-redefining-privacy-hard-choices.html#

2024-05-03 08:37:09 UTC

We are upgrading the preset SimpleX relays to the new version - it is compatible only with the apps starting from v5.5.3 (released early February) - please upgrade to the latest version and ask your friends to upgrade too.

2024-04-26 22:31:17 UTC

SimpleX Chat v5.7: better UX for calls and messages
New in v5.7:
- quantum resistant e2e encryption will be enabled for all contacts.
- forward and save messages without revealing the source.
- in-call sounds and switching sound sources.
- customizable profile images - from square to circle.
- better network connection management.
Also, we added Lithuanian interface language to Android and desktop apps - thanks to our users!
Read moret: https://simplex.chat/blog/20240426-simplex-legally-binding-transparency-v5-7-better-user-experience.html

2024-04-22 23:48:12 UTC

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@npub1rxs…u6g6 so instead of this ' try this ʼ or ՚ or ߴ - all of them should work I think.

2024-04-22 23:46:31 UTC

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@npub1rxs…u6g6 straight apostrophe is used in terminal app for the names with spaces, so it's not allowed as part of the name. You can use some of the variations - like curved apostrophe.

2024-04-19 08:51:09 UTC

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@npub1j98…meln Not really, no such option.

2024-03-23 20:37:38 UTC

SimpleX Chat: Real privacy via stable profits and non-profit protocol governance.
See the post about v5.6 release with quantum resistant end-to-end encryption and also how SimpleX network will deliver real privacy via a profitable business and non-profit protocol governance:
https://simplex.chat/blog/20240323-simplex-network-privacy-non-profit-v5-6-quantum-resistant-e2e-encryption-simple-migration.html
Esra'a Al Shafei (@npub13m2…0pq3) has just joined SimpleX Chat team to help us deliver these goals - welcome!
#privacy #security

2024-03-14 13:00:40 UTC

SimpleX Chat v5.6 beta: adding quantum resistance to Signal double ratchet algorithm!
This is a major upgrade for SimpleX messaging protocols, and I am really proud to present the results of the hard work of our whole team on the Pi day.
https://simplex.chat/blog/20240314-simplex-chat-v5-6-quantum-resistance-signal-double-ratchet-algorithm.html
You can install beta version via the GitHub release, our F-Droid repo, Google PlayStore Beta and Apple TestFlight.
Warning: this is the first beta for v5.6 release, expect some bugs!
#privacy #security #messenger

2024-02-24 21:40:13 UTC

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@npub1axx…4lsd no particular reason other than the limited time and not enough user interest to justify spending time on it. AppImage and other alternatives seem sufficient at the moment.

2024-02-24 21:39:22 UTC

Updated "SimpleX Chat Privacy Policy and Conditions of Use"
The updated document: https://github.com/simplex-chat/simplex-chat/blob/stable/PRIVACY.md
The changes: https://github.com/simplex-chat/simplex-chat/pull/3796/files
TL;DR:
- it clarifies that we develop software for communication network, and not a communication service.
- it highlights the requirement of AGPLv3 license to publish any code modifications, and our commitment to run unmodified code.
Let us know any comments or questions!

2024-02-08 16:49:24 UTC

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@npub197q…fnn4 could be a "false dilemma" logical fallacy as the assumption in 1 and 2 is that X and Y flaws are mutually exclusive, so 3 is unexpected?

2024-02-08 16:35:53 UTC

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@npub1tj5…g4sx @npub1yum…jayt thank you, there were improvements, and more are coming in v5.6 - you will be able to continue using the app while on call.

2024-02-08 16:34:50 UTC

@npub197q…fnn4 sorry if it is not the right place to ask the question about NaCl crypto_box.
In case you could answer, am I right that :
1) it does not hash the output of Curve25519 computation, and
2) it is secure to not hash it given the rest of the construction?
Thank you for your work!

2024-02-07 13:11:27 UTC

We are improving repudiation (deniability) in SimpleX protocols!
Please send any questions/comments!
We believe that repudiation is very important for private communications.
Currently only a part of SimpleX protocol stack provides it – client-to-client e2e encryption, that includes double ratchet (aka Signal) algorithm.
This proposal (https://github.com/simplex-chat/simplexmq/blob/ep/cmd-auth/rfcs/2024-02-03-deniability.md) adds repudiation to client-relay protocol.
It is already mostly implemented and will be fully rolled out by v5.7 of SimpleX Chat.

2024-01-24 20:55:37 UTC

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@npub10an…ey4e The company is registered in the UK.

2024-01-24 20:55:05 UTC

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@npub1yme…r6e2 https://simplex.chat/docs/guide/chat-profiles.html#move-your-chat-profiles-to-another-device

2024-01-24 20:54:42 UTC

SimpleX Chat v5.5 is released – with private notes and group history!
https://simplex.chat/blog/20240124-simplex-chat-infrastructure-costs-v5-5-simplex-ux-private-notes-group-history.html
Also in this release:
- simpler UX to connect - paste SimpleX links to search bar.
- improved message delivery and reduced battery usage.
- fully encrypted files and media in the app storage.
- reveal secrets in messages by tapping.
- many other improvements.
Downloads page: https://simplex.chat/downloads/
#privacy #security #messenger

2023-12-30 22:17:21 UTC

Thank you for all the support this year - it's been epic!
These are the last releases this year!
New in v5.4.2:
- faster sending messages to groups.
- lower CPU usage (except armv7 devices).
- on iOS: improved notifications and smaller video sizes
- many fixes!
In addition to that, v5.5-beta.0 has:
- new simpler UI for making connections.
- optional visible history in groups.
- reveal the secret texts by tapping.
Get them via our downloads page: https://simplex.chat/downloads/
Happy new year!

2023-11-25 20:15:10 UTC

Simplex Chat v5.4 is released – link mobile and desktop apps via secure quantum resistant protocol!
Also in v5.4:
- Many group improvements:
- faster to join and more reliable. Once you upgrade to v5.4, join the new users' group.
- create groups with incognito profile.
- block group members to reduce noise.
- Better calls: faster to connect, with screen sharing on desktop.
- Many other fixes and improvements.
Read more in the post: https://simplex.chat/blog/20231125-simplex-chat-v5-4-link-mobile-desktop-quantum-resistant-better-groups.html

2023-10-08 18:54:02 UTC

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@npub13fh…r5wz Coming in v5.4, it's in active development.

2023-10-08 18:53:28 UTC

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@npub1n8a…s6js hm, surprised myself... Pretty sure either is good, but figuring out how it happened :) thanks!

2023-10-08 18:42:19 UTC

SimpleX Chat is now available via AppImage hub!
https://www.appimagehub.com/p/2093289

2023-10-01 19:04:48 UTC

SimpleX Chat desktop for Windows is released in v5.4-beta.0!
https://github.com/simplex-chat/simplex-chat/releases/tag/v5.4.0-beta.0

2023-09-10 09:58:22 UTC

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@npub19lp…32eh I think it did it now... Added it to GitHub too, but their renderer seems to be stripping out the attributesit doesn't understand...

2023-08-19 17:41:31 UTC

You can search for public groups via the experimental **SimpleX Directory Service**: connect to it via [this address](https://simplex.chat/contact#/?v=1-4&smp=smp%3A%2F%2Fu2dS9sG8nMNURyZwqASV4yROM28Er0luVTx5X1CsMrU%3D%40smp4.simplex.im%2FeXSPwqTkKyDO3px4fLf1wx3MvPdjdLW3%23%2F%3Fv%3D1-2%26dh%3DMCowBQYDK2VuAyEAaiv6MkMH44L2TcYrt_CsX3ZvM11WgbMEUn0hkIKTOho%253D%26srv%3Do5vmywmrnaxalvz6wi3zicyftgio6psuvyniis6gco6bp6ekl4cqj4id.onion).
Mobile apps **public beta v5.3** are released:
- delivery receipts
- new layout in groups
- new UX for incognito mode
- etc.
**Desktop app** beta is now usable, please try it: https://github.com/simplex-chat/simplex-chat/releases/tag/v5.3.0-beta.5