Surf

Devices and backup

Keys live on your devices, so history is only recoverable if you set up an encrypted backup first.

End-to-end encryption means Surf cannot read your messages, and that has a consequence worth understanding before you need it: Surf also cannot restore them for you.

Chat backup

Settings, then Chat backup. A backup is encrypted with a passphrase you choose, and is sealed at rest with AES-256-GCM. The passphrase is not sent anywhere and cannot be reset by support.

  1. Open Settings, then Chat backup.
  2. Set a passphrase, or generate a recovery key and store it somewhere safe.
  3. Let the first backup complete.
  4. On a new device, sign in and restore from the same passphrase or recovery key.
Set this up while you still have the device. A backup created after a phone is lost is a backup of nothing.

Linking another device

A new device gets its own identity key and its own prekeys, and receives the sender keys it needs for the groups you are in. Because the device identity is new, the safety number in your conversations changes.

Signing out

Signing out wipes the decryption material for that account on that device. Removing an account wipes everything: device identity, sessions, group sender keys and safety-number trust records.