Privacy Policy

Last updated: April 30, 2025

Overview

ZYRN TOPO is a topographic mapping application. We are committed to protecting your privacy. This policy explains what data the app collects, how it is used, and your rights.

Data Collection

ZYRN TOPO does not collect, transmit, or store any personal data on external servers. Specifically:

• No analytics or telemetry are collected.
• No personal information is sent to any server.
• No accounts or sign-ups are required to use the app.
• No cookies are used for tracking purposes.

Local Data Storage

All app data — including map objects, settings, gear lists, and team rosters — is stored locally on your device using browser storage (IndexedDB / localForage). Map tiles viewed are cached locally using the Cache API for improved performance.

Network Requests

The app makes network requests to third-party tile servers to load map imagery. These requests are standard HTTP tile fetches and do not include any personal or identifying information. Tile servers accessed include:

• OpenStreetMap (tile.openstreetmap.org)
• OpenTopoMap (tile.opentopomap.org)
• Esri ArcGIS (server.arcgisonline.com)
• CartoDB (basemaps.cartocdn.com)
• Wikimedia Labs — Hillshade (tiles.wmflabs.org)
• OpenSnowMap (tiles.opensnowmap.org)
• BLM GIS (gis.blm.gov)
• USFS (apps.fs.usda.gov)
• Mapterhorn DEM (tiles.mapterhorn.com)
• Nominatim Geocoding (nominatim.openstreetmap.org)
• NWS Weather (forecast.weather.gov)

GPS / Location Data

If you grant location permission, the app accesses your device's GPS to display your position on the map, record tracks, and provide navigation features. Location data is stored only on your device and is never transmitted to any server.

Third-Party Services

The app does not integrate with any third-party analytics, advertising, or social media services.

Children's Privacy

ZYRN TOPO does not knowingly collect any data from children under 13.

Changes to This Policy

We may update this privacy policy from time to time. Changes will be reflected on this page with an updated date.

Contact

If you have questions about this privacy policy, contact us at grangedevgroup@gmail.com.