Effective: 21/09/2026
Who we are: Thomas Herbert, 40 Parsonage Road, Rainham, Essex, RM13 9LN (“we”, “us”). We are the controller of your personal data.
Contact: support@groundgrab.app
The short version
- Groundgrab records your location and step count only while you have started a walk, and iOS shows its location indicator while it does.
- We use that to work out which map hexes you walked, and to check that you were really walking.
- Other players can see your display name, player colour, the hexes you own, and when you claimed them. They cannot see your route, your exact position, or your email.
- We keep the raw GPS points and step counts for 90 days, then delete them.
- We don’t sell your data, show ads, or use tracking or advertising software.
- You can delete your account inside the app at any time.
What we collect, and why
| Data | When | Why |
|---|---|---|
| Sign-in identity: an Apple account identifier and the email address Apple gives us (this may be Apple’s private relay address). We do not receive your Apple password. Apple may also offer your name at first sign-in; we only use it to suggest a display name on your phone, and we do not receive it unless you choose it as your display name. | When you sign in | To create and secure your account |
| Display name that you choose | When you first choose it (at first sign-in) | So other players see who owns a hex |
| Precise location: GPS points (latitude, longitude, time, accuracy, speed, and whether iOS flags the location as simulated) | Only during a walk you start, including with the screen locked | To calculate the hexes you cover and your distance |
| Motion & Fitness data: step counts and walking distance from the pedometer, in short time windows | Only during a walk, and only if you allow Motion & Fitness | To check the walk matches genuine walking (see “Fair play”) |
| Device information: phone model, iOS version, app version, whether Motion & Fitness is allowed, whether the phone has a step counter, and any error the step counter reports | With each walk | To fix problems and to make the fair-play checks work across different phones |
| Walk results: start and end time, distance, whether it was a loop, which hexes it covered, whether it was accepted or rejected (and why), and the fair-play check results | After each walk | To run the game, keep the map correct and show you your history |
We do not collect your contacts or photos, and we do not record or save your location when you are not walking. The Map tab uses your phone’s location on the device to show where you are and to centre the map, and it asks our server for the hexes in the area you are looking at; your position is not saved to your account or sent as part of a walk. We do not use advertising identifiers.
What other players can see
Your display name, your player colour, the date your account was created, an internal random account ID (not linked to your name or email), whether the account has been deleted, the hexes you currently own, and when you claimed each one. When another player walks a hex you own, it becomes theirs. Nobody else can see your walks, your route or your email.
Fair play (automated checks)
To keep the game about walking, we run automated checks on each walk:
- Any stretch of a walk faster than walking pace (for example running or cycling) is not counted, and a walk that is entirely too fast, or too short to measure, is rejected.
- Walks that use simulated or spoofed locations are rejected.
- We compare GPS movement with your step counts. At present this comparison is only recorded so we can tune it; it does not reject walks. If we later use it to reject walks, we will update this policy.
These decisions are made automatically. If you think a walk was wrongly rejected, contact us at support@groundgrab.app and a person will review the walk and reply within 5 working days, telling you what we found. (We can only re-check a walk while we still hold its raw data; see “How long we keep it”.)
How long we keep it
| Data | Kept for |
|---|---|
| Raw GPS points and raw step counts | 90 days after the walk is uploaded, then deleted automatically |
| Walk results (times, distance, hexes covered, fair-play results), hex ownership and its history | While your account exists (see below for what happens after deletion) |
| Account details (Apple identifier, email, display name) | Until you delete your account |
| Walks stored on your phone that have not uploaded yet | Until they upload; they are erased when you sign out or delete your account |
After you delete your account
Deleting your account in the app (Walk tab, Delete account):
- deletes your sign-in details and your display name;
- immediately deletes any raw GPS points and step counts we still hold;
- releases every hex you own so it can be claimed by others.
We also delete the list of map cells each of your walks covered, and we remove the start, end and upload times and the device details (phone model, iOS and app version, motion-permission status) from your walk records. What remains is anonymised walk summaries (distance, whether it was a loop, whether it was accepted or rejected, and fair-play check statistics such as total steps) and the ownership history of the map: which cell an anonymised account owned or lost, and when. It is no longer linked to your name or email, and we do not try to identify anyone from it. Because it is a timeline of cell changes, we treat it with care, and we keep it only so the map’s history stays consistent.
Who we share it with
We use these service providers to run Groundgrab. They may only use your data to provide their service to us:
- Supabase (database, sign-in and server functions). Our data is stored in London, UK (Supabase region eu-west-2).
- Apple (Sign in with Apple, and Apple Maps, which shows the map. Apple handles map requests under its own privacy policy).
We do not sell personal data and we do not share it for advertising. We may disclose data if the law requires it.
International transfers
Our main database is located in London, UK (Supabase region eu-west-2). Apple and Supabase may process some data in other countries. Where personal data is transferred outside the UK, they rely on Standard Contractual Clauses (Supabase together with the UK Addendum to those clauses), as set out in their published terms.
Your rights and choices
- Location and Motion permissions: you can turn them off any time in iOS Settings. Without location you cannot record a walk.
- Delete your account: in the app.
- Your data rights: you can ask us for a copy of the personal data we hold about you, to correct it, or to object to how we use it, by emailing support@groundgrab.app. We will verify it is you and respond within one month. Where you ask for your data, we will send it in a commonly used, machine-readable format.
- Complain: you can complain to the UK Information Commissioner’s Office (ico.org.uk) or your local regulator.
Our legal bases (UK GDPR)
To provide the game you asked to use (contract); your permission for location and motion data (consent, which you can withdraw in Settings); and our legitimate interest in keeping the game fair and secure.
Children
Groundgrab is not for children under 13. We do not knowingly collect data from them; if you think we have, contact us and we will delete it.
Security
Data is sent over encrypted connections. Sign-in sessions on your phone are kept in the iOS Keychain. Your raw location and step data can be read only by our server, not by the app or by other players; the other data the app shows is protected by database access rules.
Changes
If we change this policy in a way that matters, we will update the date at the top and take reasonable steps to tell you before it takes effect (for example in the app or by email). The date at the top shows the latest version.