End-to-end encrypted
point-to-point messaging.
Messages are encrypted on your device with X25519 + AES-256-GCM and Signal-style forward-secret ratcheting. Our relay never sees plaintext. Add contacts by phone number or QR code. Mandatory MFA. Disappearing messages. Group chats. Delete anywhere — really anywhere.
Mission profile
Zero-knowledge relay
The relay only routes opaque ciphertext. Keys never leave your device.
Multi-device sync
Read on desktop, phone, or browser. Messages sync — and disappear — everywhere.
Disappearing
Set a TTL per conversation. Messages self-destruct on every device once it expires.
Group chats
End-to-end encrypted group sessions with sender-key ratcheting per recipient.
Add by QR / link
Invite contacts via phone number, email, scannable QR or one-shot deep link.
Delete everywhere
Tombstone a message and it vanishes from every linked device — yours and theirs.
Cryptography
- Identity · long-term X25519 + ECDSA-P256 signing key per device
- Session · X3DH-lite handshake → 32-byte conversation root key
- Per-message · HKDF-SHA256 derived AES-256-GCM key, fresh nonce, AAD-bound counter
- Forward secrecy · ephemeral DH ratchet on every outgoing message
- Verification · 60-digit safety numbers — compare in person or over a trusted channel
- MFA · TOTP plus SMS / email OTP at registration and on every new device link
Download
Platytalk is included in PlatypusTools — Security tab.
Web client (preview)
The web client uses the WebCrypto SubtleCrypto API for ECDH + AES-GCM in your browser. Keys are stored only in IndexedDB and are never transmitted.