Signal Protocol · E2EE
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.
Android APK · iPhone & desktop via the web app · Google Play soon
Signal Protocol (X3DH + Double Ratchet). Keys live only on your device; the server can never read your messages.
Messages arrive while the app is fully closed via a lightweight push wake — no draining background connection, no polling.
Sign up with just a username and password. Find people by handle — no contact-list harvesting, no SIM required.
Keys rotate with every message. A compromised key can't unlock your past or future conversations.
Photos, files, and voice notes are encrypted the same way as text — with an in-app viewer and disappearing messages.
Its own backend, identity, and infrastructure. No corporate data-mining, no ads, no tracking pixels — even on this site.
Encryption and decryption happen only on your devices. Cipher's servers store and relay ciphertext and public prekeys — never plaintext, never your private keys. There is nothing on our side to hand over or leak.
Read the FAQBecause it isn't. Install Cipher and start a private conversation in under a minute.