Privacy policy

1. What this policy covers

This policy covers two apps with a shared account and server:

• The Measure app tests how precisely a phone can measure its position using satellites (GNSS) and RTK corrections. Results serve you and, with your consent, also build a phone leaderboard.
• RTK.my turns a phone with a connected GNSS receiver into an RTK reference station (base) and sends its corrections to NTRIP casters (section 3d).

It explains what data the apps process, why, for how long, and what rights you have. Sections 2, 3, 3b, 4, 5, 8 and 10 apply only to the Measure app, section 3d only to RTK.my. The other sections (3a, 3c, 6, 7, 9 and 11–14) apply to both.

2. What stays on your phone only

Regardless of consent, the app processes on your phone:

• your precise position and raw GNSS measurements – the test cannot run without them,
• sensor data (motion, tilt, air pressure etc.) during the detailed test – to tell whether the phone lay still,
• the recording and result of the detailed test, so you can come back to the result,
• the history of corner checks (measured position, cadastral boundary corner, result),
• projects with measured points, lines and areas and photos or videos of points (without EXIF and location metadata – the app also removes any location written by the camera); with your consent they are also stored on the server (section 3); you can export them yourself (by sharing a file),
• Android's own position (the phone's system location) – shown on the map right after start, before the RTK calculation refines the position; we do not send it anywhere.

If you turn on Mock phone location (MOCK), the app passes the position from its own calculation to Android, which provides it to other apps on your phone. What they do with it is governed by their own policies.

The short test (about 1 minute) is neither sent nor stored.

3. What we store on our server – only with your consent

With your consent we store on our server the data needed to save and process your measurements and to run the app's features. It falls into these categories:

• Location data – the precise location of the places you measure (tests, points, lines, areas, corner checks, tests on a verified point), including Android's own position during a measurement.
• Measurement data – raw GNSS measurements, received corrections, computed positions and their precision, sensor data (motion, tilt, compass, air pressure etc.) and the results of tests and measurements.
• Content you create – projects, names and descriptions of points, photos, videos and other attachments to measurements, your answers about the measurement conditions.
• Device and app data – phone manufacturer and model, Android and app version, GNSS chip features and technical data needed to run the service and fix errors.
• Identifiers and account – a random installation identifier (unrelated to device identifiers or your Google account). If you sign in with Google, also your Google account identifier, email and profile photo (section 3a).

A precise location is personal data, especially if you measure at your home or on your land. We do not collect data that the app does not need for the feature in question.

The app downloads the list of RTK stations for the map from our server without your position (the phone computes the distance to stations). We only store the number of downloads per day with the installation identifier, to protect the service from abuse (legitimate interest, Art. 6(1)(f) GDPR).

Purposes:

1. refining and verifying your result (post-processing on the server),
2. the phone leaderboard – aggregated results per phone model; the leaderboard contains no locations and nothing that could identify you,
3. developing and validating new versions of the calculation on real measurements,
4. storing your measurements, projects and corner checks so you can access them on all your devices,
5. running, securing and improving the app's features,
6. promoting the service with aggregate statistics – e.g. the average accuracy of phone models, rankings and charts on the website or in articles. We use only summaries without locations and without anything that could identify you. We never use your photos, videos, measurements or places for promotion without your explicit permission, and we do not share data with advertising networks.

Legal basis: your consent (Art. 6(1)(a) GDPR).

3a. Signing in with Google

Signing in is optional. You can use the app without it. You sign in and out in the app under Settings → Account.

When you sign in, the data you stored on the phone without signing in is added to the account. After signing out, the data stays with the account and the phone keeps working without signing in.

When you sign in with Google, Google gives us your account identifier, email, name and profile photo. We store the account identifier, the email and the profile photo. We discard the name once the sign-in is verified. We scale the photo down and store it with us in the EU; it is shown only to you on your devices. We show it to other users only if you explicitly switch that on. We delete the photo when the account is deleted. We do not ask for access to your contacts, calendar, files or any other data of your Google account.

Purpose: to have your measurements, projects, photos and corner checks on all your devices, to identify you when you ask about your data, and to link your data to your account securely. We use the email only to answer your questions and for important notices about the service (e.g. a change of terms), never for advertising.

Legal basis: performance of a contract – providing the account and synchronisation under the terms of use (Art. 6(1)(b) GDPR).

Retention: as long as the account exists. We delete the account and all its data at your request (in the app or following the instructions at measure.my/delete-account) or after 5 years without using the app.

Google processes data during sign-in as an independent controller under its own policy (policies.google.com/privacy). We do not use data from your Google account for advertising, do not sell it, do not pass it to third parties other than the processors listed in section 6, and do not use it to train artificial intelligence models.

The use of information received from Google APIs adheres to the Google API Services User Data Policy, including the Limited Use requirements.

3b. Ratings, comments and reports on points and stations

If you are signed in, you can rate survey control points and RTK stations with stars, comment on them, add photos to comments on points and report the condition of points. Ratings and comments are public: other users of the app see them under your nickname, or as "Measure.my user" if you set none. We never show your email, name or Google profile photo to others. Photos are shown only after approval; the app and the server remove the location and other metadata from them. Condition reports on points are shown only as totals (counts). You can also report a problem with an RTK station (for example that it does not connect, drops out often or gives an unreliable FIX) with a short note. Only our moderation sees the report; other users see only the number of reports by type of problem. A report never switches the station off by itself.

Purpose: information about points and stations for other users. Legal basis: performance of a contract under the terms of use (Art. 6(1)(b) GDPR). We process reports of content and moderation based on our legitimate interest in a safe service and because of obligations under the Digital Services Act (Art. 6(1)(c) and (f) GDPR).

Retention: until you delete them. When the account is deleted, ratings, comments, approved photos, condition reports on points and station problem reports remain as "anonymous user", without any link to you; photos not yet approved are deleted. If a comment contains your personal data and you want it removed, write to us.

3c. Our own caster and RTK bases

Since 31 October 2026 the caster and bases belong to the RTK.my service; its separate policy is at rtk.my/soukromi. Summary:

If you are signed in, you can connect your RTK base to our caster caster.rtk.my (with the RTK.my app, a WiFi NTRIP Master module or other equipment). We store the name of the base, its mountpoint, its password only in a form that cannot be read back (a hash), its visibility and notification settings, the antenna and where it stands if you enter them, hardware details the app finds out (receiver, module, phone model) and the state of its data stream (connection, outages, availability). You grant us a non-exclusive licence to the data stream of the base (passing it on to other users, statistics, RINEX files, position computation).

Recording and position of the base. We record the data stream of every base and use it to compute the precise position of the base antenna against reference stations (EUREF/EPN, ČÚZK) and by PPP, and to watch that it does not move. The caster inserts the verified position into the stream rovers receive (RTCM messages 1005/1006, L1 phase centre). A base is verified / verified with a warning / not verified / unstable; you get an email when this changes. Other users see the base on the map only once it is verified and only roughly (position rounded to about 1 km); you see it at once. A rover that connects to the base always gets the precise position, otherwise corrections would not work.

Caster security. We log login attempts of bases and clients (time, mountpoint, IP address and provider network, result; never the password) and a fingerprint of the base (receiver, antenna, signals), to recognise a stolen password or forged data. If in doubt, the caster temporarily stops passing the base's data to rovers and you get an email.

Purpose: running the caster, determining and watching the position of bases, protecting users from wrong or forged corrections and informing the operator of the base. Legal basis: performance of a contract (Art. 6(1)(b) GDPR); login log and base fingerprint: legitimate interest in a secure caster (Art. 6(1)(f) GDPR).

Retention: the recorded stream at full rate for 14 days, decimated (one sample every 30 s) for 2 years; position results and base details until you delete the base or the account; the login log for 90 days. Deleting the base or the account also deletes its recorded data, results and NTRIP logins.

3d. The RTK.my app

RTK.my reads data over USB from a GNSS receiver connected to the phone and sends its RTK corrections (RTCM 3 messages) where you choose. It does not use the phone's Android location and does not ask for it. RTK.my does not need the data-sharing consent of the Measure app (section 3), because it sends no measurement records to the server.

On your phone stay the receiver settings, including the base coordinates you enter or the receiver surveys, the list of casters and their login details. Passwords are stored encrypted (Android Keystore) and never reach us.

On our server we process:

• a random installation identifier – created at the first connection to the server and used to secure it (unrelated to device identifiers),
• your Google account, if you sign in (section 3a) – signing in is needed only for our caster; other casters and the local caster work without it,
• bases on our caster caster.rtk.my, their data stream and the computation of their position (section 3c), including the antenna, its placement and hardware details from the setup wizard,
• in the testing phase also a check for a new app version (about once an hour, with the installation identifier and nothing else).

Position of the base. By its nature the correction stream contains the precise position of the base antenna (RTCM messages 1005/1006). If the base stands at your home, this is personal data. Our caster computes and verifies it and shows it to others on the map only roughly (section 3c); a rover that connects to the base, however, always gets the precise position from the corrections, otherwise they would not work.

Other casters. If you set up another caster in the app (e.g. RTK2Go, Emlid Caster or your own), the phone sends it the data stream of the base, including its precise position, and the login details you entered. The operator of that caster is an independent controller, may publish the data (e.g. in a station list) and follows its own terms; it may be based outside the EU (RTK2Go: USA). The choice and the responsibility are yours.

Local caster. If you switch it on, the phone accepts connections from rovers in your network directly, without our server. The app only shows details of connected rovers (network address, count) and does not store them.

Purpose: running the base and delivering corrections as you set it up. Legal basis: performance of a contract under the RTK.my terms of use (Art. 6(1)(b) GDPR). Installation identifier and server protection: legitimate interest in a secure service (Art. 6(1)(f) GDPR).

Retention: data on the phone until you uninstall the app or clear its data; bases and account as in sections 3a and 3c. You can delete the account with its bases directly in RTK.my (About → Delete account). RTK.my sends no error reports.

4. Error reports

When the app crashes or an error occurs, a technical report is sent: time, app version, phone model, Android version, test state and a technical description of the error. The report contains no location and no login details. Legal basis: legitimate interest in a working and secure app (Art. 6(1)(f) GDPR). We keep reports for 24 months, then delete them.

5. RTK correction and satellite data services

For precise measurement the phone connects directly to a correction provider (a network of reference stations) during the detailed test. With VRS-type services the phone must send the provider its approximate position (NMEA GGA messages) so the corrections can be computed for it. The correction provider is a separate controller of this data and follows its own terms.

Depending on your settings, the app connects mainly to these services:

• CZEPOS (Land Survey Office, Czech Republic),
• ASG-EUPOS (Główny Urząd Geodezji i Kartografii, Poland),
• SKPOS (Geodesy, Cartography and Cadastre Authority of the Slovak Republic, Slovakia),
• EUREF-IP / BKG (Bundesamt für Kartographie und Geodäsie, Germany) – satellite orbits, no phone position,
• RTK2Go (SNIP, USA) – test option only,
• any other correction service you set up yourself.

6. Who has access to the data

We do not sell or publish your data. The public phone leaderboard contains only summaries without locations.

• Hetzner Online GmbH, Germany – servers and storage in the EU (processor under a data processing agreement).
• Public services and map providers – the Czech Office for Surveying, Mapping and Cadastre (ČÚZK), the Geodesy, Cartography and Cadastre Authority of the Slovak Republic (ÚGKK SR), OpenFreeMap (OpenStreetMap), Mapterhorn and Esri (the Esri World Imagery satellite map). The app downloads maps and open cadastral data from them. They see your IP address and the area shown, for some requests a position rounded to at least 10 m, never your precise measured position.
• RTK correction providers (section 5) – for VRS services, the approximate position of the phone.
• Google – distribution of the apps via Google Play and sign-in (section 3a), if you use it. Android's own position (section 2) comes from the location services of your phone.
• Operators of other casters that you set up in RTK.my yourself (section 3d) – the data stream of the base including its precise position.
• Seznam.cz, a.s., Czech Republic – email mailbox and sending of notifications (section 3c).

These services process data as independent controllers under their own policies.

Transfers outside the EU: we do not transfer data from the apps outside the EU, except RTK2Go (USA) or another caster outside the EU if you choose it yourself (in the Measure app as a correction service, in RTK.my as a caster for your base). Terrain shading from Mapterhorn is delivered by the Cloudflare network (USA, certified under the EU-US Data Privacy Framework). The Esri World Imagery satellite map is provided by Esri (Environmental Systems Research Institute, Inc., USA, certified under the EU-US Data Privacy Framework); from zoom level 7 the app does not download Esri tiles that lie wholly in the Czech Republic or Slovakia and shows the ČÚZK and ÚGKK SR orthophotos instead. Cloudflare and Esri see your IP address and the area shown, not your measured position.

7. Who processes your data

The controller of your personal data is Robin Palička, a natural person, Czech Republic.

Contact for data protection matters: hello@measure.my. Website: measure.my.

We have not appointed a data protection officer, as we are not required to.

8. How long we keep data

• Test recordings and results: for as long as your consent lasts. If you do not use the app for 5 years (no connection to the server), we delete your data. Reason for this period: phones are used for several years and the recordings serve to validate new versions of the calculation on the same phone models. Raw measurements contain locations and cannot be anonymised, so after this period we delete them entirely.
• Summaries in the phone leaderboard without location and without identifier: for as long as the leaderboard exists. They are no longer personal data.
• Data on the phone: until you uninstall the app or clear its data.
• Emails you send us: 24 months, then we delete them.

9. Your rights

You have the right to:

• withdraw your consent at any time – in the app under Settings → Data ("Withdraw consent and delete my data"). Withdrawal deletes all your data on our server and the measurement history on the phone; only anonymous summaries in the phone leaderboard without location and without your identity remain. Withdrawal does not affect the lawfulness of processing before it,
• access your data and receive a copy,
• rectification, erasure and restriction of processing,
• data portability,
• object to processing based on legitimate interest (error reports),
• lodge a complaint with a supervisory authority – in the Czech Republic the Office for Personal Data Protection (uoou.gov.cz), or the authority of your EU country of residence.

Send requests to hello@measure.my. Because we do not collect your name or email without sign-in, please include your installation identifier (shown in the app under Settings → Data) so we can find your records. If you are signed in, it is enough to send the request from your account's email. We reply within one month.

You can also delete your data yourself with the Withdraw consent and delete my data button in the Measure app: it withdraws consent, deletes your records on the server and on the phone, and creates a new installation ID. The account is shared by the Measure app and RTK.my; deleting it removes it from both apps, including bases. Instructions, also without the app, are at measure.my/delete-account.

10. Automated decision-making

The test result (the phone's level) is produced automatically but has no legal or similarly significant effect on you. We do not profile people.

11. Security

Data is transmitted encrypted (HTTPS/TLS) and stored in the EU with restricted access. Login details for correction services and casters are stored encrypted on the phone and never reach us; the phone sends them only to the service or caster they belong to.

12. Children

The app is not intended for children under 16. If you are under 16, do not give consent to data sharing.

13. This website

The measure.my website uses no cookies or tracking tools and loads no third-party content. It runs on our server in the EU (Hetzner, Germany). When you visit, the server technically processes your IP address and browser details to deliver the page to you and protect it from attacks.

14. Changes to this policy

We may update this policy. If what we send and why changes, we will ask for your consent again in the app. The current version is always at measure.my/privacy.

Effective from 10 October 2026 · last changed 3 November 2026