Cipher

Private messaging,
end to end.

Cipher encrypts every message with the Signal Protocol — forward secrecy, no phone number, and battery-efficient delivery even when the app is closed. The server only ever sees ciphertext.

⬇ Download for Android How to install

Android APK · Google Play listing coming soon

🔒 True end-to-end encryption

Signal Protocol (X3DH + Double Ratchet). Keys live only on your device; the server can never read your messages.

🔋 Built for battery

Messages arrive while the app is fully closed via a lightweight push wake — no draining background connection.

🙈 No phone number

Sign up with just a username and password. Find people by handle — no contact-list harvesting.

Installing the APK

  1. Tap Download for Android above.
  2. When prompted, allow installing apps from your browser (Settings → “Install unknown apps”).
  3. Open the downloaded cipher.apk and tap Install.
  4. Launch Cipher, create an account, and start messaging.

Cipher will also be published on the Google Play Store — this direct download is for early access.