Alcatraz Messenger

Alcatraz Messenger is a decentralized, local-first encrypted messenger. Messages are encrypted on your device, delivered directly to your contact when possible, and handed to relays for asynchronous delivery when they are not.

HOW IT WORKS
- End-to-end encryption for direct messages and groups (Noise-style handshake with a Double Ratchet), so relays only handle ciphertext.
- Direct peer-to-peer delivery first, with relay mailboxes as fallback when your contact is offline or unreachable. Relays are independent third-party servers. A delivery path setting lets you choose Prefer direct or Relay only (hides your IP address from contacts, somewhat slower).
- Your history lives on your phone in an encrypted SQLCipher database. There is no email or phone-number sign-up.
- Choose your network: pick from open relays, add your own relay by address, and let the app switch to a healthy one.
- Nearby discovery: with Offline Mesh enabled, the app can find peers on the same local network and queue messages until a peer appears.
- Optional Connect with nearby people (off by default): shake or tap Find nearby people to swap contacts, Android to Android (uses Nearby devices permission). Name and ID are shared only after you both confirm the same 6-digit code. Android to iPhone is not supported; use a QR code.

MESSAGING
- Direct chats, group chats and channels with threaded comments.
- Channels are encrypted. Public channels publish their key in the directory so anyone can read them; invite-only channels are joined by invite link.
- Photos, videos and files, with in-app video playback.
- Voice messages.
- Reactions, replies, edit, delete and forward.
- Bookmarks: save a message with a link back to its chat. Bookmarks stay on this device and are not offered for disappearing messages.
- Optional disappearing-message timer per chat (1 hour, 1 day or 1 week).
- Add contacts by QR code or share your ID. Receive text, images and files shared from other apps.
- Storage controls to cap the local media cache.
- Files that pretend to be photos, videos or audio but are really programs or archives are flagged as suspicious and never shown as media.
- Searchable settings and a Profile tab for your details, linked devices, bookmarks and notes.
- Report, hide and block tools: reports on channel content go to channel admins, other reports go to support.

PRIVACY AND CONTROL
- PIN-protected vault with optional biometric unlock, and automatic lock after 15 minutes of inactivity.
- Panic PIN: entering it wipes the local vaults and keys.
- Decoy vault: a different PIN opens a separate vault with unrelated placeholder content.
- Recovery phrase and multi-device pairing to carry your identity to a new device.
- Push notifications are wake-ups that carry no message text; the message is decrypted on your device. While the app is locked you may see a generic "New message" with no sender or text.
- No ads and no in-app purchases.

GOOD TO KNOW
- Channel encryption is not confidentiality for public channels, because their key is public. Network operators and relays can still see technical connection details such as IP addresses.
- The panic PIN and decoy vault are privacy tools, not a guarantee against a determined forensic examination.
- Alcatraz is an early release (0.1.x) and is under active development. Voice and video calls are not available.

Website: https://getalcatraz.app
Support: https://getalcatraz.app/support
Privacy policy: https://getalcatraz.app/privacy