Council Private messaging and calling.
A Council group forms when its members share a passphrase. Each member's device turns that passphrase into encryption keys, so messages, calls, and media are encrypted before they leave your phone; our servers store and relay ciphertext we can't read. When the conversation is over, burn the network and the keys are destroyed.
Your network comes from a passphrase, not your contact list.
When you create a network, you choose a passphrase and pass it to people however you like: in person, on paper, over a channel you already trust. Each member's device derives the encryption keys from that passphrase using Argon2id. What reaches Council's servers is ciphertext to store and relay. Reading the conversation takes the passphrase plus a device that is already a member.
What happens to your data
We use your phone number only to create and secure your account.
It receives your sign-in verification codes. We store a password hash and salt, never the plaintext, and the app doesn't request access to your contacts or use your number to suggest or map connections. Server request logs (IP address, user agent, timestamp) are kept for 30 days for security, then purged. The privacy policy lists every field we hold.
Calls are encrypted with the same network keys.
Voice calls, one to one or with the whole group, are encrypted end to end using keys derived from the network passphrase. Audio is sealed frame by frame on your device, and the server relays the sealed packets. Incoming calls ring full screen, lock screen included. There is no dialer and no call log in the cloud.
The protocol's only asymmetric primitive is ML-KEM-768.
Key encapsulation uses ML-KEM-768, the NIST post-quantum standard; symmetric operations are AES-256 and SHA-512. There is no elliptic-curve or RSA cryptography in the protocol for a future quantum computer to break. That matters now, because traffic recorded today can be decrypted once the hardware exists.
Keys are derived on your device, with Argon2id.
Your device turns the passphrase into keys locally, and network secrets travel sealed to each member device's ML-KEM key, so there is no server-mediated key exchange to compel. A leaked passphrase alone isn't enough to decrypt a network's history, either: that also takes a secret held on a member's device.
Burning deletes immediately.
Burning a network triggers a cascade delete on the server: the key material and the records are destroyed at once, not flagged for a later cleanup. Deleting your account works the same way. Ciphertext without its keys cannot be decrypted.
No signature ties a message to you.
Messages are authenticated with keys shared by the network's members, so authenticity is scoped to the group rather than to individuals: any member could, in principle, have produced any message. There is no per-person digital signature tying your words to your identity. The network is the trust boundary.
Get Council
The app is free to download for iOS and Android. As a launch promotion, your first year of Council Pro (unlimited networks, unlimited use) is included, with no credit card required; after that it's $29.99 per year.