Features
Everything a private conversation needs
Lumen pairs the mature Matrix encryption stack with an interface designed for people who just want to talk safely.
Messaging
- End-to-end encrypted direct messages and group rooms, on by default
- Replies, reactions, edits and deletions
- Typing indicators, read receipts and presence (where the server enables it)
- Delivery states taken from real server events: sending, sent, seen
- Encrypted file and image sharing with in-browser decryption
- Search across the messages your device can decrypt — locally, never on the server
- Browser notifications, with message previews off by default
Identity & verification
- Emoji (SAS) verification between people and between your own devices
- Cross-signing: verify a person once, trust all their verified devices
- Clear warnings when someone's identity changes
- Per-message and per-room encryption indicators that tell the truth — unencrypted rooms are labelled as such
- Session list for every device, with remote sign-out
Recovery
- Encrypted server-side key backup (Matrix secure backup)
- Recovery key generated on your device and never sent to us
- Account recovery with MFA recovery codes, email reset (when configured) or assisted recovery
Accounts & teams
- Two-factor authentication: authenticator apps, security keys (WebAuthn) and recovery codes
- Workspaces with owners, admins and members
- Invitations by link or email, with seat limits enforced on the server
- Workspace policy: require MFA before members can sign in to chat
- Self-service data export and account deletion
Network
- Federation with independently operated Matrix servers
- Works with standard Matrix apps
- Operator-defined federation policy: open, allow-list or closed
- TLS 1.3 everywhere, with hybrid post-quantum key exchange where supported
Voice & video
- One-to-one voice and video calls using WebRTC (DTLS-SRTP media encryption)
- Call setup messages are end-to-end encrypted in encrypted rooms
- Available when the server operator enables the TURN relay. Group calls are not part of this release.
Ready when you are.
Create an account, or read how the security works first.