SILNT
Security
Privacy beyond the screen lock.
Encrypted conversations protect what you send. App locking and Lockdown help protect who can open SILNT. The controls below describe SILNT on iPhone.
SILNT
Your messages
For your chat only.
End-to-end encryption means only the people in your conversation can read it. SILNT cannot read your messages, photos or voice notes.
Private conversations
App lock
An unlocked phone is not an open chat.
With Lock when backgrounded enabled, leaving SILNT locks the app. Opening it again requires authentication, even if the phone is already unlocked.
Enable in Settings
Lockdown
A passcode alone is not enough.
Turn on Lockdown to require your enrolled Face ID or Touch ID to reopen SILNT. It also turns off message previews. Knowing the phone's passcode alone does not open your locked chats.
Optional extra protection
Security explained
What this means for you
Free and Pro use the same message encryption.
Private conversations
Your messages are encrypted before they leave your device. Our delivery service passes them along without being able to read them.
Removing someone from a group stops them reading new messages. They may still have copies of earlier messages or receive copies shared by another member.
Encryption and post-quantum protection
SILNT uses Messaging Layer Security, or MLS, through OpenMLS. New chats default to hybrid key exchange combining ML-KEM-768 with X25519. This is designed to protect message content against attacks that collect encrypted traffic now to decrypt it with a future quantum computer.
The hybrid suite uses AES-128-GCM, SHA-256 and Ed25519 signatures. It follows the IETF's draft for post-quantum MLS cipher suites, which is still work in progress. Ed25519 authentication remains classical; this is not a claim that every part of the app or wallet is post-quantum.
Existing chats keep their original suite. You can also choose classic encryption when creating a chat. Classic chats use X25519 with ChaCha20-Poly1305, SHA-256 and Ed25519, without the hybrid post-quantum key exchange. Check the chat's encryption setting or Post-quantum tag to see which it uses.
MLS provides forward secrecy and post-compromise recovery through key updates. Recovery requires fresh key updates after a device compromise has ended; it cannot secure a device while an attacker still controls it. The MLS specification describes these properties and their limits.
The comparison's score of 3 applies to hybrid chats; classic chats score 2. It records protocol features, not an independent security audit or equivalence to another app with the same score.
Your recovery phrase
Your twelve recovery words restore your identity and wallet. Restoring contacts and chat history also needs an encrypted backup.
Anyone with those words can access your identity and funds. Never share them, including with SILNT support.
When someone else has your phone
App locking closes access to chats and the wallet until you authenticate again. For stronger protection, turn on Lockdown and leave message previews off.
Previews let SILNT read messages to show a notification without asking you to unlock the app. Keeping them off reduces exposure if someone gains access to the phone.
These controls protect a locked SILNT session. They cannot guarantee safety if the phone's operating system is compromised or someone gains access while SILNT is already open. Some wallet records rely on the phone's own security.
Disappearing messages, Delete for everyone, view-once messages and erasing local data cannot remove copies that someone else has saved. Delete for everyone and view once work through the other person's app, so an out-of-date or modified app can keep a copy, and another camera can photograph a screen. Read the device privacy guide before changing security settings.
What services can still see
Encryption hides message content. Services still handle information such as delivery times, file sizes and the identifiers needed to deliver messages.
A public @handle and some identity records are visible to others. Payment providers can see payment details. Read the data privacy guide for the limits.
A wallet you control
You control the keys to your wallet. SILNT does not hold your funds.
Send bitcoin and USDt in a chat or use Wallet. Always check the asset and network before sending. Your @handle is for finding you in SILNT, not a payment address.