Forget the family safe-word. Ask for the HiSign.
AI can clone almost any voice in seconds. So HiSign replaces “hello” with a phrase pair only the two of you can see. Say it, and you both know the other phone still holds the secret you exchanged in person.
On the App Store and Google Play · No account, ever.
Your phone and theirs, each showing its current phrase. You read yours aloud and the other person checks it against their app, then the other way round. New pair every 60 seconds — sped up here so you can watch.
The problem
A familiar voice isn’t proof anymore.
A few seconds of audio is all it takes to clone someone you love. The call sounds exactly right, until you ask for something an impersonator would have to already know.
The voice is right. The panic is right. None of it proves anything.
You both glance at your apps. The words match — both phones are holding the secret you exchanged in person.
How it works
Set it up once, in person. Then it is two words at the start of a call.
Trade HiSigns in person — your parents, your partner, your business manager.
Trade HiSigns in person
When you’re together, tap your phones or scan a QR code. The secret is created on the two devices and nothing leaves the room.
Open the app to see your phrase
HiSign shows you a short two-word phrase, unique to the two of you and to this minute. Your contact has their own, and your app shows what theirs should be, too.
Say it instead of “hello”
Trade phrases at the start of the call. If the words match what your apps are showing, both devices hold the established relationship secrets for this minute. If they don’t, hang up.
Why it holds up
Simple to say. Hard to guess.
Two words is all anyone has to say. The math behind them is doing the work.
Nothing to phish
Every phrase is derived from the secret you exchanged in person. There’s nothing to phish and nothing an attacker could talk their way into.
Fresh every minute
A new phrase appears every 60 seconds. Even if someone overhears one, it’s worthless moments later. There’s nothing to write down or replay.
Yours alone
Your contacts and keys live only on your phone, behind your device biometrics or passcode. No accounts, no servers, nothing in the cloud to leak.
Two more places it goes.
For families and individuals
Parents and adult children, carers, one-person businesses, landlords and tenants.
For families and individualsPrivacy
You’re in control.
HiSign collects no personal data, because there’s no HiSign server for it to send anything to.
- No accounts, no sign-in
- No analytics, no tracking, no ads
- Encrypted on your device
- Locked behind Face ID, Touch ID, Optic ID, or your device passcode
- Exchange is peer-to-peer (NFC or QR)
- Works fully offline