Knock
Consent-based encrypted messaging.
A private messenger built on Matrix, running on our own server. Messages are end-to-end encrypted, and nobody talks to you until you let them.
What it does
End-to-end encrypted by default
Messages, photos, voice notes and files are encrypted on your device. Our server stores ciphertext it cannot decrypt, and neither can we.
Consent before contact
Messages from someone new arrive as a request, not in your inbox. Nobody gets your attention until you agree to give it.
No phone number
You sign up with a handle and an email address. Your number is never asked for, so it can never be leaked or looked up.
Built on Matrix
An open, federated protocol on a server we run ourselves — not a walled garden owned by an advertising company.
App Lock
Optional fingerprint, face or PIN lock on the app itself. Biometric data never leaves your device.
Delete means delete
Account deletion happens from inside the app, immediately, with no grace period and no recovery — including retiring your handle for good.
Knock started from a simple objection: every mainstream messenger assumes that anyone who has your number is entitled to your attention. Knock inverts that. A message from someone new arrives as a request, and until you accept it they cannot tell whether you have seen it, ignored it or blocked them.
The rest follows from the same instinct. There is no phone number to leak or look up — you sign up with a handle. Messages are end-to-end encrypted, so the server we run holds ciphertext it cannot decrypt. Push notifications carry only the fact that something arrived, never what it said. There is no advertising SDK, no analytics SDK, and no third-party tracker in the dependency tree at all.
It is built on Matrix, an open federated protocol, on a server we operate ourselves in the EU.
Legal & support
These pages are the public URLs referenced in the app’s store listing.