Privacy policy for the app “SELFTEST”
This English version is for information only. Only the German version is legally binding.
Android app. As of 2 November 2026.
This privacy policy informs you, pursuant to Art. 13 of the General Data Protection Regulation (GDPR), about which personal data the Android app SELFTEST processes, for what purpose it does so and what rights you have.
1. Controller
The controller within the meaning of the General Data Protection Regulation (GDPR) is:
Geier-IT – Anton Geier, Untere Bergstraße 2, 55487 Sohren, Deutschland. Email: info@geier-it.eu. Telephone: +49 152 04202892.
Further information can be found in the Impressum (legal notice). There is no statutory requirement to appoint a data protection officer.
2. The key points in brief
- SELFTEST works without a user account and without a server of the provider. As the provider, we receive no data from the app.
- The app contains no advertising and no analytics, tracking or crash reporting services.
- Test reports and measurement files are transferred exclusively to the cloud server that you enter in the app yourself.
- For the map extract in the report and for the place name, the position of the test point is transmitted to map services (section 4).
3. Which data the app processes
3.1 Details in the settings
Name of the person carrying out the test (“Carried out by”), company, address of the cloud server, user name, password and target folder. This information is stored exclusively on your device in the internal storage of the app. The password is encrypted with AES-256-GCM; the key is held in the Android Keystore and does not leave the device. Name and company appear in the test report.
3.2 Location
With your permission, the app reads the precise location when you connect the measuring device, at the first drop of each measurement series and – if no position is available by then – when sending. From this, coordinates, UTM coordinates and the place name of the test point are produced for the test report and measurement files. The app does not query the location in the background. Without permission, the measurement continues to work; the report and files then contain no location information.
3.3 Bluetooth
The app searches for Bluetooth devices nearby and displays their names for selection. Only the Bluetooth address of the most recently selected device is stored. The Bluetooth search is not used to determine location.
3.4 Measurement data
From the light weight deflectometer (Fallgewichtsgerät), the app takes over the device number, calibration data and the settlements, velocities and settlement curves of the drops. Together with date and time, location, name and company, these produce a PDF test report and measurement files in JSON and TTD format.
3.5 Bluetooth recording
The app records the data transmission with the measuring device: times, raw data transmitted, and the name and Bluetooth address of the device. The recording makes the measurement traceable and helps with troubleshooting. It is transferred to your cloud server with each measurement and is automatically deleted from the device after 30 days.
4. Recipients and transmission
4.1 Your cloud server (WebDAV)
When sending, the app transfers the test report, measurement files and recording to the server that you have entered in the settings, and creates a folder there for each measurement. It also accesses this server for the connection check and the folder selection. The operator of the server is responsible for processing on the server, for example your employer or your hosting provider. If the server uses HTTPS, the transfer is encrypted; we recommend entering HTTPS addresses only.
4.2 Map extract – OpenStreetMap
For the map extract in the test report, the app downloads map tiles from the map server tile.openstreetmap.org of the OpenStreetMap Foundation (United Kingdom). In doing so, your IP address, the map tiles requested – from which the approximate location of the test point can be derived – and an identifier of the app are transferred. An adequacy decision of the European Commission exists for the United Kingdom (Art. 45 GDPR). Privacy policy of the OpenStreetMap Foundation: osmfoundation.org/wiki/Privacy_Policy. Map data © OpenStreetMap contributors, Open Database License.
4.3 Place name – geocoding service of the device
The app determines the place name via the geocoding service of the Android system. In doing so, the coordinates of the test point are transmitted to the provider of this service; on devices with Google services, this is Google Ireland Limited, Gordon House, Barrow Street, Dublin 4, Ireland. Google may also process data in the USA; Google LLC is certified under the EU-US Data Privacy Framework. Google's privacy policy: policies.google.com/privacy.
4.4 Location services of the device and Google Play
The position itself is supplied by the Android system (GPS or the location services of your device). Which data these services process depends on the settings and terms of your device manufacturer or of Google, respectively. When the app is downloaded via Google Play, Google processes data under its own responsibility.
Beyond this, the app does not pass any data on to third parties, does not sell any data and does not use data for advertising.
5. Legal bases
- Art. 6(1)(b) GDPR: provision of the functions you use – measurement, test report and upload.
- Art. 6(1)(f) GDPR: legitimate interest in complete and traceable test documentation, including location, map extract and recording.
- Access to location and Bluetooth requires your permission in the permission prompt of Android. You can withdraw it at any time in the system settings.
6. Storage period
| Data | Storage on the device |
|---|---|
| Settings and access credentials | until you change them, delete the app data or uninstall the app |
| Test report and measurement files | until successful upload; after that they are deleted from the device |
| Bluetooth recordings | 30 days, then automatic deletion |
| Location and place name | only as part of the test report and measurement files |
On your cloud server, the deletion rules of the server operator apply.
7. Permissions of the app
| Permission | Purpose |
|---|---|
| Location (precise and approximate) | Coordinates, UTM coordinates and place name of the test point |
| Nearby devices (search for and connect via Bluetooth) | Connection to the light weight deflectometer |
| Internet and network status | Upload (also in the background, as soon as a network is available again), map extract and place name |
8. Data security
Settings, access credentials and measurements not yet sent are located in the internal storage of the app, to which other apps have no access; the password is additionally encrypted. Settings, access credentials, measurements not yet sent and recordings are excluded from the Android backup and from the transfer to a new device.
9. Your rights
You have the right of access (Art. 15 GDPR), rectification (Art. 16), erasure (Art. 17), restriction of processing (Art. 18), data portability (Art. 20) and objection to processing based on legitimate interests (Art. 21).
Since we, as the provider, receive no data from the app, you delete the data on your device yourself: in the Android settings under Apps › SELFTEST › Storage › Delete data or by uninstalling the app. For data on the cloud server, please contact its operator.
You also have the right to lodge a complaint with a data protection supervisory authority (Art. 77 GDPR), for example with the authority competent for us: Der Landesbeauftragte für den Datenschutz und die Informationsfreiheit Rheinland-Pfalz (State Commissioner for Data Protection and Freedom of Information of Rhineland-Palatinate), www.datenschutz.rlp.de.
10. Children
SELFTEST is aimed at professionals in the construction sector and is not intended for children.
11. Changes to this privacy policy
We amend this privacy policy if the app or the legal position changes. The version published at this location at any given time applies.
Contact
Please direct questions about data protection to: info@geier-it.eu