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SimpleX ChatSignal
Free

Free and open source under the AGPL 3.0. The company is funded by investment and…

 Free

Free; developed by a nonprofit funded by grants and donations

Windows, macOS, Linux, Android, iOS, Command line Android, iOS, Windows, macOS, Linux
  • No user identifier of any kind, so conversations cannot be correlated by account
  • Double ratchet encryption with an additional layer for the relay servers
  • End-to-end encryption on every message and call using the open source Signal Protocol
  • No ads, affiliate marketers or tracking
  • Connecting means exchanging a link or QR code in person or elsewhere
  • No contact list means a lost device is a lost set of conversations unless backed up
  • Requires a phone number that can receive an SMS or phone call to register
  • Desktop app requires Signal to be installed on a phone first
Downloadable app Downloadable app
Open source Open source
License: AGPL-3.0 License: AGPL-3.0
No account needed Account needed
Works offline Needs internet

Checked September 21, 2026

Checked September 20, 2026

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