What you'll sign when you start Radius.

The short version

• Your location comes from your phone. It's usually within a few meters outdoors, but it can be a street off or lag minutes behind. Positions are kept 10 days, then deleted.
• Your location is never sold or handed to a data broker, and Radius carries no advertising at all.
• Messages and photos are stored on Radius's server for 14 days, then deleted. They aren't end-to-end encrypted, so the server operator could technically read them.
• Calls connect directly between phones or pass through Radius's relay, and no part of any call is ever recorded.
• Weather alerts can arrive late or not at all. Speeding alerts are conversation starters for families and aren't evidence. Hard braking is a rough signal, never proof of how somebody drives.
• Crash detection can miss a real crash or go off by mistake. It's never a substitute for calling 911.

This summary is here to help. It isn't part of the Acknowledgment, and it isn't what you sign. The full text below is what counts.

1 · Location

Your position comes from your phone — GPS, Wi-Fi and cell signals — and is drawn on a map. Accuracy varies: usually within a few meters outdoors, but it can be a street off indoors, in cities, or in bad weather, and it can lag minutes behind when a phone is asleep or out of signal. Positions are kept 10 days, then deleted automatically. Only people your family manager has connected you with can see you. Your location is never sold, never handed to a data broker, and never used to work out what to advertise to you — Radius carries no advertising at all and is paid for by the people using it.

2 · Messages, photos and calls

Messages and photos travel over encrypted connections and are stored on Radius’s server for 14 days, then deleted; keeping a conversation longer is your choice and lives on your own phone. Like a text message with your carrier, message content on the server is not end-to-end encrypted — the server operator could technically read it, and you should know that rather than assume otherwise. Voice and video calls are different: they connect directly between phones and are never stored. When a direct connection is impossible, the call passes through a relay server (STUN/TURN) run by Radius — the relay forwards encrypted packets it cannot open, and no part of any call is recorded, ever.

3 · Severe weather alerts

Warnings come from the National Weather Service and are matched to each person’s last known position. They can arrive late — network delays, a sleeping phone — or not at all, and their accuracy is the NWS’s, not ours. Weather alerts are a convenience, never a substitute for official warnings, sirens, or your own judgment. Alert text is processed transiently and not kept.

4 · Speeding alerts (when available)

Speed comes from GPS, which mismeasures during turns, stops, and poor signal. Speed limits come from OpenStreetMap community data hosted on Radius’s servers — many roads, especially rural ones, have no recorded limit or an outdated one, and no alert fires on those. Alerts can be delayed and events are kept only under the same retention as location history. Speeding alerts are conversation starters for families, not evidence — they must not be used for discipline based on a single reading, insurance, or legal purposes.

5 · Hard braking (when available)

Detected from your phone’s own motion sensors while driving. Every phone is different — newer or older, better or worse sensors, mounted or loose in a pocket — so two phones in the same car can disagree. A hard-braking event means the phone felt something abrupt, nothing more: a pothole, a dropped phone, or a genuinely hard stop all look similar. Treat it as a rough signal about a drive, never as proof of how somebody drives.

6 · Crash detection (when available)

Radius watches for the pattern of a crash — highway speed, a violent jolt, then stillness — using phone sensors and GPS together. It can miss real crashes and it can false-alarm on drops and rough roads, which is why a suspected crash first asks the driver “Are you okay?” with a countdown, and only silence alerts the family. It needs battery, signal and location to work, and it is delayed by its own countdown by design. It is NEVER a substitute for calling 911. If you can call for help, call for help.

While you are sharing

Radius shows a notification whenever it is sharing your location, so it is never running quietly in the background. Nobody is added without approval, and you can pause sharing or leave at any time.