TradeCert Privacy Policy

This policy explains what happens to data when you use TradeCert (“the app”), published by Anvil Labs (“we”, “us”). It is written to be read, not to be impressive. If anything here is unclear, email support@anvillabs.app.

1. Information we collect ourselves

Nothing, unless you join the leaderboard. TradeCert still has no sign-up, no login, no password and no email-based account. If you never opt in to the leaderboard, nothing about your studying is sent to us, and we cannot see how you answer questions or how you score. If you do opt in, we receive exactly the items listed in section 3 and nothing else.

2. Information stored on your device

The following is written to your device’s private app storage and never transmitted to us:

• Study progress — attempts, best score and last score for each category.
• Premium status — whether the one-time unlock has been purchased, stored in Android’s encrypted storage so the app works offline.
• App preferences — such as when the app last checked for a content update.
• Leaderboard identity — if you join the leaderboard, the app also keeps your profile identifier and recovery code here so the board recognises you.

Uninstalling the app, or clearing its data in Android settings, removes all of it. If you joined the leaderboard, your profile on our server is separate and is not deleted by uninstalling — see section 7.

3. The optional leaderboard

The app includes an online leaderboard. It is strictly opt-in: nothing in this section happens unless you choose to join. If you do join, the app sends the following to our server over an encrypted (HTTPS) connection:

• A nickname you choose — public: it is displayed on the leaderboard to other users, so pick one you are happy to show.
• A country, and optionally a region or state, that you select — public. This is a menu choice, not your location: the app never asks for location permission and never reads GPS.
• An avatar — one of 24 preset icons, stored as nothing more than a number — public.
• Your scores for the three boards — correct answers this week, best survival run, and best streak run — public.
• A random profile identifier that our server generates, and a recovery code, so you can get your profile back after reinstalling the app.

That list is complete. Joining the leaderboard sends your profile choices and board scores — not your study progress, your notes, your settings, or anything else on the device.

4. Identifiers we never store in readable form

Running a public leaderboard fairly requires some abuse prevention. Three identifiers are involved, and none of them is stored in readable form:

• Your IP address is never stored. The server keeps only a keyed one-way hash (an HMAC) of it, used for rate limiting and abuse prevention.
• A recovery identifier is derived on your device from the Android device ID using a keyed one-way hash. The raw Android ID never leaves your phone.
• Your recovery code is stored on the server only as a keyed one-way hash. The readable code exists in exactly one place: the app on your device.

5. What we still do not collect

Even if you join the leaderboard: no email address, no real name, no phone number, no contacts, and no location — the country on your profile is something you picked from a menu, not a reading from your device. The app also contains no analytics or crash-reporting SDK of any kind. We do not track how you use it.

6. How long leaderboard data is kept

Your leaderboard profile and its data are kept for as long as the profile exists. The boards themselves reset on their weekly and monthly cycles by design, so board scores are replaced as part of normal operation. If you ask us to delete your profile, everything attached to it goes with it — see the next section.

7. Deleting your data

Leaderboard profile: email support@anvillabs.app and tell us the nickname on the profile you want removed. We will delete the profile and its scores from the server, which also removes you from the boards.

Everything on your device — study progress, settings and your local leaderboard identity — is deleted by uninstalling the app or clearing its data in Android settings. That part has never required our involvement.

Never joined the leaderboard? Then we hold nothing about you, and uninstalling the app removes everything there is.

8. Third-party services used in the app

The app uses the following Google services. Each has its own privacy policy, and each may process device-level information such as an advertising identifier, IP address, and general device and usage signals:

Google’s handling of this data is governed by the Google Privacy Policy. You can reset or delete your advertising ID at any time in Android Settings under Privacy → Ads.

9. Advertising choices

Purchasing the premium unlock removes all advertising from the app permanently. Ads never appear during a timed mock exam. Where required by law, the app presents a consent prompt before personalised advertising is shown, and your choice is respected.

10. Payments

All purchases are handled by Google Play. We never see or store your card details, billing address, or any payment information. Refunds are handled through Google Play under its standard refund policy.

11. Children

TradeCert is intended for adults preparing for occupational certification exams. It is not directed at children under 13, and we do not knowingly collect information from them.

12. Your rights

If you never joined the leaderboard, we hold no personal data about you, so there is nothing for us to export or delete on request — uninstalling the app removes everything. If you did join, the data we hold is the profile described in section 3, and you can email support@anvillabs.app to ask what it contains or to have it deleted, as described in section 7. To limit ad personalisation, use the Android advertising ID controls described above.

13. Changes to this policy

If this policy changes materially, the date at the top of this page will change and the updated version will be published here before the change takes effect in the app.

14. Contact

Anvil Labs — support@anvillabs.app