Privacy Policy – WiFi Stride
Version 1.1 – 31 October 2026 Controller: BIA.BZH, French sole trader (micro-entreprise), Brest, France, SIREN 943 008 151 – contact: contact@bia.bzh
The French version of this policy prevails; this translation is provided for convenience.
In short
- WiFi Stride does not collect, store on servers, transmit or share any data about you. The app does not request the Internet permission: the Android system forbids it any network communication.
- Everything the app measures (Wi‑Fi networks, mobile network, motion, height, optionally the camera image) is processed only on your phone; the current survey is saved in the app's private storage and nowhere else.
- The only files created are those you export (PNG images, CSV file), saved on your phone under your control.
- No analytics, advertising or crash‑reporting tool is included.
- The only exception, independent of BIA.BZH: if you enable camera tracking (off by default), Google's ARCore component sends technical data to Google (see § 4).
1. Data processed on the device
To work, the app processes the following information locally. None of it is transmitted to BIA.BZH or to any third party by the app.
| Information | Why | Where it goes |
|---|---|---|
| Wi‑Fi scan results: name (SSID), technical identifier (BSSID), signal level, frequency of surrounding networks | Build coverage maps and recognise places already visited | App memory and private storage (automatic save of the survey); export files if you request them |
| Mobile network: technology (2G to 5G), operator, signal level and quality, cell identifiers (cell ID, PCI, TAC, channel, band) | Build mobile network coverage maps (4G, 5G…) | App memory and private storage (automatic save of the survey); export files if you request them (cell identifiers appear in the mobile network CSV file) |
| Motion sensors: steps, acceleration, orientation (gyroscope, optional magnetometer), atmospheric pressure if the phone has a barometer | Estimate your movement through the building and floor changes | App memory; only estimated positions appear in the automatic save and in exports |
| Name (SSID) of the Wi‑Fi network the phone is connected to, read when a survey starts, and the networks you mark as yours | Offer the “My network” map, limited to your networks | App's private storage (automatic save); title and name of exported maps if you export |
| Project name you enter when starting a survey | Identify the survey and name its export folders | App's private storage (automatic save); export folder names if you export |
| Camera image (only if you enable ARCore tracking) | Estimate the phone's movement precisely | Processed in real time by ARCore on the device; never recorded or displayed by the app |
The app does not read your geographic location (GPS, network): the location permission is required by Android to access Wi‑Fi scan results and mobile network cell measurements, and the app uses it for those purposes only. Cell identifiers could in principle be used to roughly locate the place surveyed: they stay on your phone and only appear in the exports you create. It creates no account, uses no advertising identifier, and reads neither your contacts, nor your files, nor your other apps.
2. Permissions requested and their use
| Android permission | Use in WiFi Stride |
|---|---|
Precise location (ACCESS_FINE_LOCATION) |
Condition imposed by Android to read Wi‑Fi scans and mobile network cells; no position is read or stored |
Nearby Wi‑Fi devices (NEARBY_WIFI_DEVICES, Android 13+) |
Read Wi‑Fi scans |
Physical activity (ACTIVITY_RECOGNITION) |
Use the phone's step sensor |
Camera (CAMERA) |
Only if you enable camera tracking (ARCore); can be disabled at any time |
| Wi‑Fi state and change | Trigger Wi‑Fi scans; the app connects to no network |
The app does not request the INTERNET permission.
3. Retention and deletion
The measurements of the current survey are saved automatically in the app's private storage (a
folder that Android reserves for the app and that no other app can read), so that the survey can be
resumed if the app is closed or interrupted. They are deleted when you finish the survey (“Export ▸ Finish the survey”, with or without
exporting), when you decline to resume a survey offered at launch (including “Export all, then
delete”), and when the app is uninstalled. A save that has become unreadable is not deleted
right away: it is set aside in the same private storage, the app tells you, and it is deleted in
the same cases. Your settings are kept the
same way. This storage is excluded from Android backup and from transfer to a new device
(allowBackup disabled, data extraction rules that exclude everything): nothing is copied to
Google, any other service or another phone.
Exported files are saved in Pictures/WiFiStride/<project> and Download/WiFiStride/<project> on
your phone; you can
view, share or delete them with any file manager. Uninstalling the app does not delete exported
files.
If you have enabled automatic photo backup (for example Google Photos) for the Pictures folder,
your exported images may be copied by that service under its own rules; this is a setting of your
phone, not of the app.
4. Third‑party services
- Google Play Services for AR (ARCore): if you enable camera tracking, position computation is performed by this Google component, installed separately and running in its own process. Motion tracking is performed on the device and the app does not use the ARCore features that send images or a location to Google (Cloud Anchors, Geospatial). This component, provided by Google, is governed by the Google Privacy Policy. According to Google, when it is used it sends to Google, over an encrypted connection and for analytics purposes: a device identifier (or your Google account identifier if you are signed in), performance diagnostics (battery life, loading time, latency, frame rate) and information on the app's use of its features. This data goes directly from the component to Google: BIA.BZH has no access to it. It is declared in the "Data safety" section of the Google Play listing. To avoid it, leave camera tracking disabled: the app then works from your steps.
- Google Play: distribution and updates of the app go through Google Play, which applies its own privacy rules.
Apart from these cases, no third party is involved.
5. Third‑party data contained in your exports
Wi‑Fi scans list surrounding networks, including your neighbours' (name and technical identifier of their access points). This information is broadcast publicly by the access points and is only used locally. The mobile network CSV file contains the identifiers of the measured cells, which could be used to roughly locate the place surveyed. If you share your exports, you are responsible for that distribution.
6. Your rights
Since the app collects no personal data, BIA.BZH holds no data about you and therefore has nothing to disclose, rectify or erase under the General Data Protection Regulation (GDPR). You may nevertheless write to us with any question at the address given at the top of this document. You have the right to lodge a complaint with your supervisory authority (in France, the CNIL, https://www.cnil.fr).
7. Minors
The app is not specifically directed at children and collects no data, whatever the user's age.
8. Changes
Any change to this policy will be published at this address with a new version date. In case of a substantial change (for example if a future version were to collect data), the app will inform you before enabling the feature concerned.
9. Contact
BIA.BZH – Brest, France – contact@bia.bzh