Privacy Policy

Offline Local Architecture

TopoNode is built as an offline-first professional surveying and GIS tool. It has no user accounts, it contains no analytics, advertising or crash-reporting service, and MEDEV Studios does not run a server for it or receive your survey data.

Your projects, surveyed points, lines, parcels, surfaces, instrument observations, feature codes and correction-server settings are stored in the app's private Room (SQLite) database on your device. This database is not encrypted. It is protected by Android's app sandbox, which keeps other apps from reading it. Point photos, imported and offline maps, and the app's own backup files are kept in the app's storage folders on the device.

The password for your NTRIP correction server is not stored in the database. It is kept in a separate file, encrypted (AES-256) with a key held in the Android Keystore. If the Keystore is unavailable on a device, the password is kept in the app's private storage without encryption. The password is never written to the app's backup files.

The app's settings also hold the surveyor name, company and header note you enter for reports, the map sources you add, and the address of the last Bluetooth receiver you connected. Errors are written to a diagnostic log kept on the device; the app does not send it anywhere.

Correction Servers and Online Maps

TopoNode uses the internet only to reach services that you configure yourself. MEDEV Studios does not receive any of this data; each service's operator handles it under its own terms.

• NTRIP correction servers. When you turn on an NTRIP connection, the app connects to the caster you enter or pick from the built-in list (TUSAGA-Aktif or RTK2go) and sends your caster username and password. While connected, it sends your receiver's current position (latitude, longitude, height and time, as an NMEA GGA sentence) to the caster about every 10 seconds, so that the caster can produce corrections for your location. Loading a caster's list of mountpoints also sends your username and password. Unless you turn on TLS for that caster, the credentials and positions are sent unencrypted.
• Online basemaps. TopoNode has no built-in online basemap. If you add an XYZ, WMTS or WMS map source, the app downloads map images from that server for the area shown on the map, or for an area you choose to save for offline use. These requests reveal your IP address and the map area requested to the server's operator, and identify the app by name and version. MBTiles files you import are read from the device and need no connection.

Sharing, Exports and Backups

When you export or share data, such as survey files, reports, photos, raw GNSS logs or a backup, TopoNode hands the file to the app or storage location you choose; it does not upload files anywhere itself. Reports include the surveyor name, company and header note you have entered. Backup files contain your project data and point photos, and your NTRIP host, mountpoint and username, but not your NTRIP password.

Automatic backups are written to the app's storage on the device every 6 hours and whenever you leave the app, and the newest 10 are kept. You can turn this off in Settings.

If Android backup is turned on for your device, Android may include TopoNode's settings and other app files, such as point photos, in your Google account backup. The survey database, the NTRIP password, the diagnostic log and the app's backup files are excluded from that cloud backup. During a direct device-to-device transfer, the survey database and other app data may be copied to the new device, but the NTRIP password is not.

Permissions

• Location (precise and approximate) is required to use the app. It is used to read the phone's own GNSS position and raw satellite measurements, and to show your position on the map. Positions are saved when you record points, and raw measurements only when you record a raw GNSS log. For a first approximate fix, the app may also use Android's network location provider. TopoNode does not request background location access. Your position and survey data leave the device only in the ways described above.
• Bluetooth (nearby devices) is required to use the app on Android 12 and later. It is used to list the GNSS receivers and total stations paired with your device and to connect to them. The Bluetooth scan permission is declared as not being used to determine your location. Android 11 and earlier use the older Bluetooth permissions for the same purpose.
• Camera is optional. It shows the live camera view in AR stake-out mode, which is displayed on screen and not recorded. Point photos are taken with your device's camera app and saved in TopoNode's storage.
• Notifications are optional. They are used to show the ongoing notification while a receiver connection or a phone GNSS session is running.
• Foreground services keep a receiver connection and a phone GNSS session running while the screen is off or another app is in front. The phone GNSS service is started only while TopoNode is in the foreground.
• Internet, network state and Wi-Fi state are used for NTRIP connections and online basemaps. The Wi-Fi state permission is added by the MapLibre map library.
• Vibration is used for haptic feedback.
• Background work (wake lock, start at boot) is added by Android's WorkManager library, which the app uses to schedule its automatic local backups.

You can revoke any permission in your device's Android settings.

Your Choices and Deletion

You can delete projects and map sources in the app, turn off NTRIP and automatic backups, and turn on TLS for a caster. Uninstalling TopoNode deletes everything it stores in its own storage on the device, including its automatic backups. Files you have exported or shared to other apps or locations are not affected. Data received by a correction server or map server you configured is held by that server's operator; contact them about it.

Contact Us

For questions or support regarding TopoNode, contact MEDEV Studios at info@medevstudios.com.