Privacy Policy

Version of October 12, 2026

Who processes your data

SQL Casebook is developed by a private individual listed as the seller on the app's App Store page ("we"). We determine the purposes and means of processing your data. You can contact us through the Feedback section in your profile or via the support contacts on the app's page.

What data we collect

Account: email, username, display name (if you provided one) and your password, which is stored only as a hash. Progress: solved clues, number of attempts, hints used, dates and the text of your last query for a clue. Awards: which ones you earned and when. Feedback: text, category, your account email for the reply, app version, device model and language. Technical data: IP address and request times in server logs.

Guest mode

You can use the app without registering. In that case we create an anonymous account with no email or name and link progress, awards and feedback to its random identifier. Guest data can be deleted in the profile, and data of a guest who has not opened the app for 60 days is deleted automatically. If a guest creates an account, their progress moves into that account.

What we do not collect

We do not use advertising, tracking or third-party analytics SDKs, and we do not track you across other apps. SQL queries run on your device; only the text of your last query for a clue is sent to the server.

Why and on what legal basis

Your account and progress are needed to provide the service and sync your learning across devices (performance of a contract). Feedback is needed to answer you and fix errors (legitimate interest). Technical data is used for security and abuse prevention (legitimate interest).

Who receives the data

Data is stored by Supabase Inc. in a data centre in Frankfurt (EU). Supabase processes it only on our instructions. Feedback is forwarded to the support mailbox via Resend (Resend, Inc., USA). We do not sell your data or share it for advertising. We may disclose data only in response to a lawful request from public authorities.

Anonymous statistics

To understand which cases are hard and where the app is inconvenient, we collect anonymous events: which case or task was opened, whether a clue was solved, whether a hint was opened, plus the interface language and app version. Events are stored in the same Supabase database in Frankfurt (EU) and are not linked to your account, email or name, the text of your queries is never sent, and no advertising identifiers are used. You can turn this off: Profile → Anonymous statistics.

Transfers outside the EU

Supabase and Resend are US companies. If data is transferred outside the EU while providing the service, the transfer is protected by the European Commission's Standard Contractual Clauses.

How long data is kept

Account, progress and feedback are kept while the account exists. When you delete the account they are removed from the database immediately; they may remain in the provider's backups for up to 30 days. Server logs are kept for no longer than 90 days.

Your rights

You can get a copy of your data (Profile → Download my data), correct it (Profile → Name and username), delete your account with all data (Profile → Delete account), and object to or restrict processing by writing to us. EU and UK residents may lodge a complaint with their national data protection authority. Residents of California and other US states have the right to know what data is collected and to request its deletion; we do not sell or "share" personal information as defined by the CCPA.

Children

The app is not intended for children under 16, and we do not knowingly collect their data. Age confirmation is required at sign-up. If you learn that a child has created an account, write to us and we will delete the data.

Security

The connection to the server is encrypted (HTTPS), passwords are stored only as hashes, and access to database rows is limited to the account owner. No system is completely secure, so please use a strong password.

Changes to this policy

We may update this policy. We will tell you about material changes in the app. The date of the current version is shown below.

Support email: support@sql-casebook.com