Masteries Privacy Policy
Last updated: October 24, 2026
Masteries is a general knowledge app. This policy explains which data the app uses, why, who it is shared with, and how to exercise your rights.
In short: Masteries shows no ads, does no ad tracking and sells no data. You can play without an account; your progress then stays on your phone.
1. Who is responsible for your data
Léo Bodoulé Sosso, sole trader (French micro-entreprise), SIRET 992 115 634 00014, 34 rue de Boves, 80090 Amiens, France.
Contact: contact@masteries.app
2. The data we use
Without an account
- On your phone only: your progress, hearts, coins, coin purchases, settings, news quiz results and, if you choose one, your profile picture. This data never leaves the device.
- Your answers to the welcome questionnaire (daily goal, motivation, level, favourite categories, app language), sent with a random identifier specific to the installation, which does not identify you.
- If you allow notifications: the technical token used to send them, with the device's language and system (iOS or Android).
- If you report a question: the reason you chose and, if you write one, your comment.
With an account
In addition to the above:
- your email address, used to sign in (a code is sent to you each time);
- your display name and username, if you set them;
- a backup of your progress, exams, coins and hearts, so you can find them on another phone or after reinstalling;
- the app version, the device's system and the date of your last visit.
If you subscribe
Payment goes entirely through Apple (App Store) or Google (Google Play): we never receive your payment details. To know whether your subscription is active, the app uses the Adapty service, which receives information about your purchases (product, dates, status), technical device identifiers and, if you are signed in, your Masteries account identifier.
3. Why we use it
| Purpose | Legal basis |
|---|---|
| Running the app: learning path, progress, account, backup, sign-in by code | Performance of the contract (the terms of use) |
| Managing your subscription and purchases | Performance of the contract |
| Sending you reminders and notifications | Your consent, given through the phone's permission and withdrawable at any time in its settings |
| Improving the content and the welcome flow (questionnaire answers, question reports) | Our legitimate interest in offering accurate, suitable content |
| Keeping our accounts | Legal obligation |
We do no advertising, no advertising profiling, and no automated decision-making with legal effects on you.
4. Who receives it
Your data is only accessible to the publisher and to the technical providers below, which process it on our behalf and on our instructions:
| Provider | Role | Where the data is |
|---|---|---|
| Supabase Pte. Ltd. (Singapore) | Database, accounts, sign-in | European Union (Frankfurt, Germany) |
| Mailgun Technologies, Inc. (United States) | Sending the email with your sign-in code | European Union |
| Adapty Tech Inc. (United States) | Subscription management | United States |
| Expo (650 Industries, Inc.) | Delivering notifications | United States |
Apple and Google process your payments and subscriptions as independent controllers, under their own privacy policies.
When data leaves the European Union, the transfer is covered by the European Commission's standard contractual clauses (Supabase, Adapty, and Mailgun for any transfer outside its European region) and, for Adapty and Expo, by the EU-US Data Privacy Framework.
5. How long we keep it
- Account: as long as the account exists. You can delete it at any time in the app (Profile → Edit my information → Delete account): the account and all the data linked to it are erased. Technical database backups are erased within 7 days.
- Device data: erased when you uninstall the app.
- Welcome questionnaire answers without an account: 2 years after their last update.
- Reports: kept to correct the content; once the account is deleted, they are no longer linked to anyone.
- Purchase data: kept by Apple, Google and Adapty for their own periods and for our accounting obligations.
6. Your rights
You have the right to access, rectify, erase, restrict, object to and port your data, and to withdraw your consent at any time. To exercise them, write to contact@masteries.app; we reply within one month.
If you believe your rights are not respected, you can lodge a complaint with the CNIL, the French data protection authority (www.cnil.fr), or with the authority of your country.
7. Security
Exchanges between the app and our servers are encrypted. Access to data is restricted: each user can only read their own data, and only the publisher administers the database.
8. Minors
Masteries is for all audiences. If you are under 15, ask a parent before creating an account or subscribing.
9. Changes
We may change this policy, for example if the app adds a service. The date at the top of the page shows the latest version. If the change is significant, we will let you know in the app.