Trace is a ballistics reference calculator. It was built so that your data stays yours. This policy describes everything the app touches — there is nothing else.
What we collect
Nothing, on our own servers — we don't operate any. Trace has no analytics, no advertising, no tracking SDKs, and no first-party backend.
Your data and where it lives
- Rifle profiles, ammo loads, dope, custom reticle designs, and saved targets (the map coordinates of targets you mark, with their names and order) are stored on your device. If you are signed into iCloud, iOS mirrors this data to your private iCloud database so it syncs across your iPhones, iPad, and Apple Watch. That database belongs to your Apple account; we cannot read, access, or export it. Deleting the app (and its iCloud data via Settings → Apple ID → iCloud) removes it entirely. Apple's push service tells your other devices that something changed; those silent notifications carry no data of yours.
- Location (optional, "While Using the App" only): if you grant location access and tap "Use GPS," Trace reads your position to determine altitude and sends your coordinates, rounded to about 1 km, to the Open-Meteo weather API (open-meteo.com) to fetch local barometric pressure, temperature, and wind for density-altitude correction. The request contains coordinates only — no identifiers, no account information. We do not store your location; every environmental value can also be entered manually and the app is fully functional with location denied.
- Following a target (optional): when you tap a marked target to follow it, Trace keeps reading your position — including while the screen is off — so the range and bearing to that target stay current as you move. iOS shows its location indicator the whole time. This stops the moment you stop following the target, put the course away, or take over manually. Your positions are used on the device only and are not transmitted or stored beyond the current session.
- Map Range (optional): when you range or mark a target on the satellite map, Trace sends your position and the target's coordinates, rounded to about 10 meters, to the Open-Meteo elevation API (open-meteo.com) to compute the angle of fire. As with weather, the request contains coordinates only — no identifiers — and Open-Meteo does not receive anything that identifies you. Satellite imagery is provided by Apple Maps under Apple's privacy terms.
- Chronograph files (optional): importing a chronograph CSV on the Tune tab reads the file you pick, on the device, to compute an average velocity. The file is never uploaded or kept.
- Apple Watch: the watch app reads the same rifles and targets from your private iCloud database and uses the watch's own GPS, compass, and motion sensors on the wrist, under the same rules as above. Nothing on the watch leaves the watch except the same rounded coordinates sent to Open-Meteo when you capture live conditions.
- Sign in with Apple (optional): signing in stores your Apple-issued credential in your device's keychain. It is not transmitted to us — again, there is no "us" to transmit it to. The app is fully functional without signing in.
- Compass and device motion are read on-device for wind-direction and incline-of-fire capture and never leave your phone.
What we share
Nothing. No data is sold, rented, or shared with third parties, with the single exception described above: rounded coordinates sent to Open-Meteo when you request local weather or range a target on the map. Open-Meteo's privacy policy is at https://open-meteo.com/en/terms. Purchases are handled by Apple; we never see your payment details.
Children
Trace is a technical reference tool and is not directed at children.
Changes
If this policy ever changes, the updated version will be posted at this URL with a new effective date. Given the app's architecture — no servers, no accounts, no analytics — we don't expect it to change much.
Contact
Questions: Traceballistics@icloud.com