Privacy Policy

This policy covers the PrecAlgo Range apps for iOS and Android and the website at range.precalgo.com. The data controller is YUXIN ZHANG, reachable at [email protected].

The app is fully usable without signing in. Equipment parameters, ammunition data, DOPE data and photographs are held in local storage on the device and are not sent to our servers. Ballistic solving, the zeroing flow and visual ranging run on the device and require no connection.

An account is optional. When you register or sign in we process your email address and an account identifier, for authentication and cross-device restore. If you use a third-party sign-in such as Apple or Google, we receive only the identifying information needed to create the account. Signing in is not, by itself, consent to upload anything from your device. You can delete your account from within the app.

With your consent, equipment configurations (rifles, optics and ammunition) and DOPE cards are stored on our servers so they can be restored on another device. Photographs are never uploaded. Sync can be switched off at any time in settings; when you delete your account, the data already synced is deleted with it.

When you search the factory rifle, optic and ammunition catalogue, your search terms are sent to our servers so that results can be returned. When you choose automatic fill on the conditions card or the DOPE page, the app sends coordinates rounded to about 1 km to our servers, which query a weather data source for temperature and humidity; the request carries no account or device identifier, and the coordinates are not written into your records. Where the device has a barometer, station pressure is read from the device.

Photographs are stored on the device, including targets photographed during zeroing, ballistic tables photographed from ammunition boxes, and frames frozen in the visual rangefinder. Camera access is used for these captures, for the live reticle overlay and for scanning device QR codes; object recognition in the visual rangefinder runs on the device, and frames are neither stored nor uploaded. When you pick a photo from your library, the app reads only the photo you selected. Cloud backup, such as iCloud or Google Drive, is something you switch on yourself and is held by the provider you choose.

When connecting chronographs, wind meters and similar devices, scanning and testing happen on the device; no imagery or readings are uploaded. We explain what a permission is for before requesting it. Heading, incline and pressure readings from the device are used for solving and are not uploaded. Location access is used for the weather lookup, for the latitude needed by the Earth-rotation correction, and for converting the compass to true north; apart from the rounded coordinates described above, your location does not leave the device.

We do not sell your data. We do not use your data for advertising. We do not embed third-party advertising or cross-site tracking SDKs in the app.

range.precalgo.com serves static pages. It sets no tracking cookies and embeds no analytics scripts. Our host produces ordinary access logs, including IP addresses, in the course of delivering the site; these are used for security and troubleshooting.

We use the following providers: Oracle Cloud Infrastructure (API servers and database, Phoenix, United States); Supabase (accounts and authentication); Cloudflare (website hosting, CDN and forwarding of API traffic); and the Norwegian Meteorological Institute (MET Norway) and the US National Weather Service (weather data; they receive only coordinates rounded to about 1 km). They process data on our instructions and for no other purpose.

Data on your device is kept until you delete it or uninstall the app. Data you have synced is kept for the life of your account; after you delete the account, server-side data and your sign-in account with the identity service are deleted within 7 days, and copies on backup media are rotated out within 30 days.

At any time you can export a backup from within the app (a single zip containing local records and photos), delete your account and all local data, and switch sync off. For access, rectification, restriction, objection or portability, write to [email protected]. If you are in the EEA or the UK you also have the right to complain to your local supervisory authority.

Our servers are located in the United States. Where data is transferred out of your region, we rely on the transfer mechanisms required by applicable law, including standard contractual clauses where these are needed.

The app is intended for adult shooters and is not directed at anyone under 18. We do not knowingly collect data from minors.

When this policy changes we update the effective date at the top of the page, and we notify you in the app when the change is material.