SimpleX Chat

Last updated
SimpleX Chat
Developer SimpleX Chat Ltd
Initial release12 January 2022;3 years ago (2022-01-12)
Stable release
v6.4.8 [1] / December 11, 2025;27 days ago (2025-12-11)
Preview release
v6.5.0-beta.3 [2] / December 24, 2025;14 days ago (2025-12-24)
Repository
Written in Haskell
Kotlin (Android)
Swift (iOS)
Operating system
Available inEnglish, German, Spanish, Chinese, Turkish, French, Italian, Russian, Ukrainian, Japanese, Polish, Hungarian, Czech, Dutch, Finnish, Bulgarian, Thai
Type Encrypted voice calling, video calling and instant messaging
License GNU Affero General Public License
Website

SimpleX Chat is a free and open-source cross-platform end-to-end encrypted instant messaging app and console application. The app does not require phone number, email address, or any other external identification. [3]

Contents

SimpleX applications are available for Android, iOS, Windows, macOS operating systems, and various Linux distributions. [4]

History

In July 2024, the American cybersecurity firm Trail of Bits conducted an independent security audit of the SimpleX Chat's cryptographic protocols. [5]

Following the arrest of Pavel Durov in France in 2024 many extremist groups fled from Telegram to SimpleX due to heightened privacy concerns. [6] [7] [8] [9]

Funding

SimpleX Chat is developed by SimpleX Chat Ltd, a commercial company. [10] The project began full-time development in 2021, initially supported by angel investors including Portman Wills and Peter Briffett. [10] In July 2022, it raised approximately $370,000 in pre-seed funding, including from Village Global. [10] [11]

In August 2024, SimpleX Chat announced a $1.3 million pre-seed investment led by Jack Dorsey, with participation from Asymmetric Capital Partners. [6] [12] The company has stated that user donations play a significant role, covering infrastructure costs and supporting development, with collective donations exceeding $25,000 as of 2023. [10]

In November 2025, the co-founder of Ethereum Vitalik Buterin donated 128 ethers to SimpleX Chat. [13]

Russia

In September 2024 the app was blocked by Russian authorities (Roskomnadzor). [14] In September 2025, Tagansky court of Moscow fined the owning company SimpleX Chat Ltd. for "failure to fulfill the obligations of an instant messaging service provider," a violation of the law requiring every messaging application to collaborate with state authorities and, if requested, provide encryption keys for certain communications. [15]

Features

SimpleX Chat provides quantum-resistant end-to-end encryption for one-to-one chats, group conversations (called "secret groups"), and voice/video calls, using a double-ratchet protocol similar to Signal's, with an additional encryption layer per message. It requires no phone number, email, or personal details, instead using one-time invitation links, long-term invitation links (can be used more than one time) or QR codes for connections and temporary anonymous queue identifiers for message routing. Unlimited creation of profiles is supported (Incognito or not).

All user data is stored locally in an encrypted database on the device, with messages temporarily held on relay servers and deleted after delivery. Additional privacy features include "Incognito mode," which generates a random profile name and prevents sharing of the user's actual profile name or image with new contacts, as well as a two-day expiration limit for file downloads, after which files become unavailable. [8] [16] [17]

References

  1. simplex-chat. "Release v6.4.8 · simplex-chat/simplex-chat". GitHub. Retrieved 2026-01-01.
  2. simplex-chat. "Release v6.5.0-beta.3 · simplex-chat/simplex-chat". GitHub. Retrieved 2026-01-02.
  3. "SimpleX Chat: private and secure messenger without any user IDs (not even random)". simplex.chat. Retrieved 2025-11-09.
  4. "Download SimpleX apps". simplex.chat. Retrieved 2025-11-09.
  5. "SimpleX network: cryptographic design review by Trail of Bits, v6.1 released with better calls and user experience". simplex.chat. Retrieved 2025-11-09.
  6. 1 2 Makuch, Ben (2024-10-04). "Far-right extremists flee from Telegram to SimpleX over privacy features". The Guardian . Archived from the original on 2025-08-26. Retrieved 2026-01-01.
  7. Gilbert, David (2024-10-04). "Neo-Nazis Are Fleeing Telegram for Encrypted App SimpleX Chat". Wired . Archived from the original on 2024-10-04. Retrieved 2026-01-01.
  8. 1 2 Bolpagni Alessandro, Ristuccia Eleonora (2025-08-07). "Remaining and Expanding: IS Munasirin and the pro-Islamic State Ecosystem on SimpleX Chat". The Global Network on Extremism and Technology. Archived from the original on 2025-08-08. Retrieved 2026-01-01.
  9. "Wired's Attack on Privacy". SimpleX Chat blog. 2024-10-16. Retrieved 2026-01-05.{{cite web}}: CS1 maint: url-status (link)
  10. 1 2 3 4 "SimpleX Chat: vision and funding, v5.0 released with videos and files up to 1gb". simplex.chat. 2023-04-22. Retrieved 2026-01-02.
  11. Esra'a al Shafei (4 April 2024). "Why I joined SimpleX Chat". simplex.chat. Retrieved 2026-01-02.
  12. "SimpleX network: the investment from Jack Dorsey and Asymmetric, v6.0 released with the new user experience and private message routing". simplex.chat. 2024-08-14. Retrieved 2026-01-02.
  13. Katte, Stephen (2025-11-27). "Buterin donates to 2 projects pushing 'next steps' of digital privacy". Cointelegraph. Archived from the original on 2025-11-27. Retrieved 2026-01-01.
  14. "Интернет-цензура и блокировка контента российскими регуляторами". ОВД-Инфо (in Russian). Retrieved 2025-11-09.
  15. "Суд оштрафовал двоих владельцев анонимных мессенджеров за неисполнение закона РФ". РАПСИ (in Russian). 2025-09-24. Retrieved 2025-11-09.
  16. "SimpleX". Whonix Wiki. Retrieved 2026-01-05.
  17. "SimpleX Chat v5.6 (beta): adding quantum resistance to Signal double ratchet algorithm". simplex.chat. 2024-03-14. Retrieved 2026-01-06.