Secure Messaging App

A secure messaging app that assumes everyone is listening

NoChat is engineered on a zero-trust model: the network, the server, and even NoChat itself are all treated as untrusted. Every message is encrypted on-device and stays that way.

Zero-trust by designAuthenticated encryptionOpen source

Security claims are easy to make and hard to verify. NoChat is a secure messaging app where the guarantees are enforced at the protocol level, not promised in marketing copy. The server stores encrypted blobs and routes them — that's its entire job. Keys are generated on your device, content is end-to-end encrypted, the cryptography is standardized and auditable, and the whole codebase is open source so you can check every claim yourself.

Zero-trust server

A secure messaging app is only as strong as its server architecture. If the service holds your private keys, your encryption is theater. NoChat's server stores encrypted ciphertext, routes it, and nothing else. Identity keys, exchange keys, and session keys are all generated on your device — the server never sees them and could not derive them if it tried.

The threat model NoChat actually defends against

Being specific about your threat model is the difference between a serious secure messaging app and a marketing one. Here's what NoChat protects against — and the one thing no app can.

  • Network attackersISPs, public hotspots, and on-path observers see only ciphertext.
  • A compromised servera full database breach yields opaque blobs and pseudonymous IDs — nothing decryptable.
  • Tampering in transitAES-256-GCM is authenticated, so altered messages are detected and rejected.
  • Identity linkageno phone number or email is required, so there's nothing to correlate.
  • Not a malicious endpointif your own device is compromised, no messaging app can save you — that's true of every app.

Standards-based cryptography, no homegrown crypto

NoChat uses primitives anyone can audit: AES-256-GCM for content, P-256 ECDH for key agreement, HKDF-SHA256 for key derivation, and P-256 ECDSA for signatures. Calls use WebRTC with DTLS-SRTP. Post-quantum key encapsulation (ML-KEM) is implemented on the backend and on the roadmap for the client — we describe it as planned, not deployed, on the frontend.

Auditable open source

Every line of the client and server is public at github.com/kindlyrobotics/nochat. Don't trust our word — read the code, trace where keys are generated, and confirm the server schema only holds ciphertext. The full cryptographic breakdown lives in our crypto inventory.

Frequently asked questions

What makes a messaging app truly secure?

The service can't read your messages even if it wanted to, metadata is minimized, the cryptography is standardized and auditable, and there's no single point of trust. NoChat is built to hit all four.

What threat model does NoChat protect against?

Network attackers (ISPs, hotspots, on-path observers), a compromised NoChat server, and tampering in transit. The only thing it can't protect against is a malicious endpoint — if your own device is compromised, no app can save you.

How is NoChat protected against a server breach?

There's nothing useful to steal. The database holds encrypted ciphertext with no decryption keys attached. A full dump gives an attacker exactly what it gives us: opaque blobs.

Can law enforcement get my messages?

Under valid legal process we can produce account metadata where it exists, but message content is end-to-end encrypted and we have no ability to decrypt it. That's a mathematical fact about the design, not a policy choice.

Has the code been audited?

The codebase is fully open source and under continuous community review, and the cryptographic primitives are documented in the repository's crypto inventory. Formal third-party audit status is tracked on GitHub.

Does NoChat cost money?

No. NoChat is free to use and free to self-host. Security shouldn't be a paid upgrade.

Try NoChat today

Free, open source, and private by design. No phone number, no email required.

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