SCRATS

No phone number. No email. The whole messenger in two minutes, on a real iPhone and a real Android phone: - Sign up with a login, a nickname and a password - A 12-word recovery phrase restores your account on any device - Share a nickname, a QR code or a quant address instead of a number - Nobody can message you until you accept their request - Messages, photos and voice notes between iPhone and Android, encrypted on the device - Encrypted calls and built-in Tor Three days free on the App Store and Google Play: umbera.app #privacy #encryption #cybersecurity

We have published the cryptographic core of Umbera. This is the code that decides what our server can and cannot see: - Hybrid post-quantum key agreement: X25519 + Kyber (ML-KEM-1024) - Dilithium (ML-DSA-65) identity signatures - Sealed sender: the server never learns who sent a message - Rotating rendezvous addresses: it never learns who talks to whom - Double Ratchet for chats, MLS for groups - Full protocol specification Read it, run the tests, check our claims. Code: github.com/Vahe327/UMBERA App: umbera.app #privacy #cryptography #postquantum

The server is not supposed to know who you talk to. No phone number. Sealed sender. Post-quantum encryption. Open crypto core. umbera.app #privacy #encryption #postquantum #messenger

Don't trust, verify. We published a proof that only the recipient can read an Umbera message and only the participants can hear a call. Every claim can be checked: 1. Code: the sealing of every message (X25519 + Kyber, HKDF, AES-256-GCM) and the encryption of call setup are public. 2. Tests: clone the repo and run cargo test --test proof. They show the recipient opens a message, any other key fails, breaking X25519 alone is not enough, and tampering is rejected. 3. Traffic: capture a call in Wireshark. You will see a DTLS handshake, then only encrypted SRTP. The assumptions are listed too: an infected phone, or a recipient who forwards your message, is outside what encryption can solve. Proof: github.com/Vahe327/UMBERA/bl… #privacy #cryptography #postquantum

New write-up: how Umbera seals every message with X25519 + ML-KEM-1024, what our server can and cannot see, and how call setup is protected from DTLS fingerprint swaps. With Rust tests you can run yourself. dev.to/umberaapp/dont-trust-…

Even a quantum computer that breaks X25519 can't open an Umbera message on its own. Every message is sealed with X25519 + ML-KEM-1024 (FIPS 203). The key comes from both, so an attacker has to break both. A public test checks exactly this: breaking_only_x25519_is_not_enough

Umbera is a private messenger built on one rule: the server should never know who talks to whom. - No phone number, no email. Sign up with a username only. - Post-quantum end-to-end encryption for every message. - Sealed sender: the server delivers messages without seeing who sent them. - End-to-end encrypted voice and video calls, groups and conferences. - Built-in Tor support for extra network privacy. - Your message history stays on your device. App Store: apps.apple.com/app/id6805525… Google Play: play.google.com/store/apps/d… Web: umbera.app #privacy #encryption #messenger