Location-based notifications
Everything below rests on one rule: a channel asks, and the phone decides. What arrives is guaranteed; how loudly it arrives is not, and any page that told you otherwise was selling.
Draw a circle without knowing who is inside it
You place a centre and a radius on a map, and the circle travels attached to the alert. Every subscriber’s phone receives it and compares its own position locally, then decides whether to show it. No subscriber position is ever sent to us, which is why this is a design fact rather than a promise: there is no column anywhere that could hold one. Two consequences follow deliberately. A geofence only ever narrows — it cannot add somebody who did not subscribe. And it fails open: a phone that cannot work out where it is shows the alert rather than hiding it, because missing an evacuation is worse than seeing one meant for the next street.
Nothing that could identify anybody
Subscribing needs no account, no email address and no phone number. What a subscription actually holds is a random identifier the app generated, a platform, an app version, a language and a time zone — coarse enough that hundreds of millions of people share one. There is no name, no contact detail, no advertising identifier and no location, and there is no export that would let an operator build one. You cannot leak a list you never collected.
Questions, answered plainly
Do you know where my subscribers are?
No. The circle is sent with the alert and each phone compares its own position locally. We hold no subscriber location, so there is nothing to leak, subpoena or lose. A phone that cannot determine its position shows the alert rather than hiding it.
What do you collect about somebody who subscribes?
A random identifier the app generated, a push token, the platform, the app version, the language and the time zone. No name, no email address, no phone number, no location, and no advertising identifier. Subscribing needs no account at all.
Do subscribers need an account?
No. They install the app, subscribe to a handle, and that is the whole of it. Only the person running the channel signs up for anything.
How do people find my channel?
From the handle you give them: on a poster, in an enrolment email, on a QR code, in a footer. Public channels also appear in the app’s discover list. Sealed ones appear nowhere at all, by design.
Say it once. Every subscribed phone gets it.
Free up to 100 subscribers, no card to start, and the handle is yours permanently.
Start a channel