Data and privacy
Data controller
The publisher of Matlo (see the legal notice) is the controller for the processing described here. Any question: contact@matlo.app.
Data processed
Account: e-mail address, username, password (stored hashed, never in clear text), chosen language and theme. Activity: puzzles attempted, moves played, thinking time, ratings, drills, timestamps. External accounts, if you link them: Lichess or Chess.com identifier, imported public games and ratings; if you sign in with Lichess, that account's e-mail address and an access token, stored encrypted. Technical data: IP address and access logs processed by the hosting provider for the security of the service. Diagnostics: errors, response times and, if you accepted replays, when an error occurs in the application, a recording of the screen leading up to it (account identifier, pages and actions, without the content of input fields), without IP address. Site audience measurement: pages viewed, referring page and site, campaign parameters of the address (UTM, Google Ads click identifier), device type and country, with no cookie and no identifier; PostHog derives from the IP address and the browser a fingerprint valid for one day, then discards the address. Sign-up origin: the site page, campaign parameters and the site you came from, carried by the addresses up to sign-up and kept with your account. Usage measurement: your training (puzzles attempted, reviews, exercises and their answers), your key steps (sign-up, linked accounts, games imported and analysed) and your settings, tied to your account identifier, never to your e-mail address, sent by our servers (nothing is read on your device). In-app measurement and replays, only if you accepted them: the screens opened, what you tap and, during your first two weeks, a recording of your visits (input fields and displayed e-mail addresses masked), tied to your account identifier.
Purposes and legal bases
Providing the service (account, training, analysis of your games): performance of the contract. Security, abuse prevention and technical logs: legitimate interest. Error detection and fixing, performance measurement: legitimate interest. Service e-mails (password reset, security alerts): performance of the contract. Site audience measurement: legitimate interest, under the consent exemption set by the CNIL. Sign-up origin, to know how Matlo is discovered: legitimate interest. Usage measurement, to decide what to improve in Matlo: legitimate interest; you can object at any time in Settings › Privacy, and nothing more is sent afterwards. In-app measurement, replays and the diagnostic error replay: your consent, asked at sign-up, which you can withdraw at any time in Settings › Privacy. No marketing, no advertising, no sale of data.
Retention
Account and activity data: until you delete your account, which you can do yourself from Settings; deletion is immediate. Encrypted database backups: at most 30 days. Hosting provider technical logs: at most 30 days. Diagnostic data: at most 90 days. Audience, usage and in-app measurement: at most 12 months. Replays: at most 30 days.
Recipients and processors
Your data is only accessible to the publisher. Technical processors: Cloudflare (hosting of the site, the application and the API, United States, certified under the EU–US Data Privacy Framework), Oracle Cloud (database, European Union), Sentry (error and performance monitoring, data hosted in the European Union), Resend (sending service e-mails: your e-mail address and the content of the message, United States), PostHog (audience, usage and in-app measurement and replays, data hosted in the European Union, IP address not kept). Lichess and Chess.com are sources, not recipients: Matlo sends them nothing.
Transfers outside the European Union
Requests to the site and the application go through Cloudflare's global network; the database stays in the European Union. Transfers to Cloudflare, Inc. are covered by the EU–US Data Privacy Framework and the European Commission's standard contractual clauses. Diagnostic data is hosted in the European Union by Sentry (Functional Software, Inc.); any access from the United States is covered by the same safeguards. Service e-mails are sent by Resend, Inc. (United States), under the European Commission's standard contractual clauses.
Cookies
A single, strictly necessary cookie: the session cookie that keeps you signed in. It is exempt from consent. Error monitoring stores no cookie nor any other data in your browser. Site audience measurement stores no cookie nor identifier and does not track you across sites. In-app measurement and replays, if you accept them, store nothing either: everything stays in memory for the life of the page. No ad network.
External accounts
Lichess is linked through your public username, or by signing in with Lichess (OAuth): Matlo then only asks to read your e-mail address, and the Lichess account can no longer be linked by another player. Chess.com is linked through your public username, without a password. Matlo can neither play nor write on your behalf. Disconnecting an account stops any new import; analysed games stay until the account is deleted.
Your rights
Access, rectification, erasure, portability, restriction and objection: write to contact@matlo.app from your account's address, or delete your account from Settings. Answer within one month. You may also lodge a complaint with the CNIL (cnil.fr), the French data protection authority.
Security
Encrypted connections (HTTPS), hashed passwords, per-player data isolation at the database level, access restricted to the publisher. Should an incident affect your data, you will be informed by e-mail.
Minimum age
Matlo is intended for people aged 15 and over. Below that age, a parent's consent is required to create an account.
Changes
This policy may evolve with the service. The date at the top shows the last update; a significant change is announced in the application.