Privacy Policy — Cathartic

1. Who we are

Cathartic is developed and operated by Štěpán Šrubař, an individual based in Ostrava, Czechia ("we", "us"). We are the data controller for the personal data described in this policy.

Contact: gamemaster@featurehear.com

This policy covers:

the Cathartic app for Android (package com.featurehear.cathartic.android) and iOS (the "App"),
this website at cathartic.featurehear.com (the "Website"),
the browser-based study tool at cathartic.featurehear.com/study (the "Study app").

Together we call these the "Service".

2. The short version

You can play the App as a guest. In that case we do not collect any personal data about you.
If you create an account, we receive your email address and a display name. Your display name and your scores are visible to other signed-in players on leaderboards. Your email address is never shown to anyone.
If you turn on Google Drive sync, your flashcards and study history are saved into a hidden folder of your own Google Drive. We cannot read that folder.
Friends, duels and team games are optional. Players you add as friends and players you duel see your display name and your game progress, as described in section 5.
The App contains no advertising, no analytics and no tracking SDKs. We do not sell personal data.
You can delete your account at any time. See Delete your account.

3. What we process, why, and on what legal basis

The table lists every category of data the Service handles. The legal bases refer to Article 6 of the EU General Data Protection Regulation (GDPR).

When	Data	Purpose	Legal basis	Where it is stored
Playing as a guest	No personal data. The App downloads version information, decks and audio from our server and from Cloudflare, and reads feature flags from Google Firestore. Your IP address is visible to those services while the request is served.	Running the game, delivering content	Legitimate interest (Art. 6(1)(f))	Nothing is stored by us. Your progress stays on your device.
Creating an account	Email address, a display name, a technical user ID, the sign-in method (email and password, Google, or Apple), account creation time. Passwords are handled by Google Firebase and are never visible to us.	Signing you in, keeping your profile across devices	Contract (Art. 6(1)(b))	Google Firebase Authentication and Firestore (Google Cloud, EU and US regions)
Signing in with Apple (optional)	Your Apple user ID; the email address Apple shares with us, which is a private relay address if you choose Hide My Email; your name, which Apple sends only on your first sign-in and which we use only to suggest a display name; and a refresh token Apple issues for the App.	Signing you in; revoking the App's access to your Apple ID when you delete your account	Contract (Art. 6(1)(b))	Google Firebase Authentication; the refresh token in our MySQL database at Wedos; the Apple user ID on your device
Your player profile	Display name, chosen languages, study streak, in-game currency balances, best results per deck, whether Drive sync is on.	Keeping your profile across devices	Contract (Art. 6(1)(b))	Google Firestore
Finishing a game while signed in	A record of the game: your user ID, display name, email address, the deck played, win or loss, score, number of challenges done and failed, average answer speed, currency earned, time.	Leaderboards, seasonal rankings, detecting cheating	Contract (Art. 6(1)(b)); legitimate interest in fair play (Art. 6(1)(f))	Our MySQL database at Wedos (Czechia)
Leaderboards	Your display name and your scores. These are shown to other signed-in players. Your email address is never part of what other players can see.	Competitive play	Contract (Art. 6(1)(b))	Our MySQL database at Wedos; daily-trial scores in Google Firestore
Your player profile for friends and medals	Your display name, achievements unlocked, Tower of Knowledge level, campaigns completed, Conquest wins, your best tower-defence score of the month, study streak, the time of your last update, and the medals we award you for these. The App sends this snapshot when you open the main menu signed in or open your profile.	Showing your profile to your friends, awarding medals, monthly medal rankings	Contract (Art. 6(1)(b))	Our multiplayer server at Oracle Cloud (European Union)
Friends	Whom you asked to be friends, who asked you, when, and whether the request was accepted. When you ask a player who has not used the feature yet, we keep the display name you found them under with the request, and nothing else about them.	The friends list, visiting a friend's Tower of Knowledge	Contract (Art. 6(1)(b))	Our multiplayer server at Oracle Cloud (European Union)
Duels	Your display name, rating, wins and losses on each ladder, and a record of every duel: both players' names and user IDs, the result and the ratings before and after. During a duel your opponent is shown the names of your decks so you can agree on one; the fixed emotes you exchange are relayed and not stored.	Matchmaking, ratings and duel leaderboards	Contract (Art. 6(1)(b))	Our multiplayer server at Oracle Cloud (European Union)
Team Conquest games	The name you give a game, who you invited and who invited you, your user ID and display name on the shared board, and who last saved it.	Playing Conquest together with your friends	Contract (Art. 6(1)(b))	Our multiplayer server at Oracle Cloud (European Union)
Minigame saves	The state of your Tower of Knowledge and of your Conquest games, with a revision number and the time of the last change.	Keeping these minigames in step across your devices, showing your Tower of Knowledge to your friends	Contract (Art. 6(1)(b))	Our multiplayer server at Oracle Cloud (European Union)
Moderation	If we restrict or ban an account: the restriction, its reason and its expiry. Every action taken by an administrator is written to an audit log together with the administrator's own IP address.	Enforcing fair play and our Terms	Legitimate interest (Art. 6(1)(f))	Google Firestore and our MySQL database at Wedos
Google Drive sync (optional)	Your whole study collection: decks, flashcards including any text you typed, your review history, media files, and up to three daily backups.	Backing up and syncing your study data across devices and with the Study app	Consent (Art. 6(1)(a)), withdrawable at any time	A hidden application folder in your own Google Drive. We have no access to it. See section 4.
Reminders (optional)	Your chosen reminder time.	Local study reminders	Consent (Art. 6(1)(a))	Your device only. Reminders are scheduled by the operating system; nothing is sent to us or to a push service.
Writing to us	Your email address and whatever you write, including the Apple ID email address you send us to join the iOS beta on TestFlight.	Answering you, adding you to the TestFlight tester list	Legitimate interest (Art. 6(1)(f)); for TestFlight access, contract (Art. 6(1)(b))	Our mailbox; for iOS testers, the TestFlight tester list in App Store Connect
Server connection logs	We have switched off access and error logging on our web hosting. Our hosting provider still processes your IP address for the duration of a connection in order to deliver it and to protect its network.	Delivering the Service, security	Legitimate interest (Art. 6(1)(f))	Wedos (Czechia), transiently
Multiplayer server logs	Operational logs of the multiplayer server: user IDs, duel room codes and error messages. They contain no IP addresses. The server keeps no access log.	Keeping the multiplayer server running, finding faults	Legitimate interest (Art. 6(1)(f))	Our multiplayer server at Oracle Cloud (European Union); deleted after 30 days

Text-to-speech in the App uses the speech engine built into your device's operating system. The App does not send the spoken text to us. Depending on your device settings, the operating system may use an online speech service; that is governed by your device vendor's privacy policy.

We do not collect your location, contacts, photos, microphone or camera input, advertising identifiers, device identifiers, or crash reports. The only identifier we hold is the user ID of your account.

4. Google Drive sync and Google API Services

Drive sync is off by default. When you turn it on, the App asks Google for permission using these scopes:

https://www.googleapis.com/auth/drive.appdata — read and write the App's own hidden application folder in your Google Drive,
openid, email and, when you sign in with Google, profile — to know which Google account you connected and to show your name.

The App never requests access to your other Drive files. The application folder is not shown among your regular Drive files, and only Cathartic (the App and the Study app, which share one Google Cloud project) can open it. We, the developer, have no way to read it; it lives entirely in your Google account.

The App stores the access and refresh tokens it receives from Google in an encrypted file on your device so you do not have to sign in again. Tokens are never sent to our servers.

To stop syncing, turn Drive sync off in the App. To remove the stored data, open Google Drive on the web, go to Settings → Manage apps, find Cathartic and choose Delete hidden app data. To revoke the App's access entirely, open your Google Account → Security → Third-party apps & services and remove Cathartic.

Cathartic's use and transfer of information received from Google APIs adheres to the Google API Services User Data Policy, including the Limited Use requirements.

5. Who receives your data

We do not sell personal data, and we do not share it with advertisers or data brokers. The following companies process data on our behalf so that the Service can work:

Google LLC — Firebase Authentication, Cloud Firestore, the Google Drive API, the Google Sign-In SDK on iOS, and Google Fonts on the Website. Google Privacy Policy, Firebase privacy information.
Apple Inc. — Sign in with Apple, when you choose it. Apple confirms who you are and tells us only what is listed above. Apple Privacy Policy.
WEDOS Internet, a.s. (Czechia) — hosting of our web server and MySQL database.
Cloudflare, Inc. — hosting of downloadable example decks.
Oracle Corporation (Oracle Cloud Infrastructure, European Union) — hosting of our multiplayer server, which holds the profiles, friends, duels, team games and minigame saves listed in section 3. Oracle Privacy Policy.

Other players can see some of your data. Choose a display name you are comfortable showing publicly.

Everyone signed in sees your display name and your scores on leaderboards. Anyone who searches for players by name sees your display name, Tower of Knowledge level, number of medals and study streak.
Your friends additionally see your profile (achievements, campaigns, Conquest wins, tower-defence score), your duel ratings and record, your medals, and can visit your Tower of Knowledge.
Your duel opponent sees your display name, rating and the names of your decks. A duel room you open as public shows your display name, rating and chosen deck to anyone who opens the duel lobby.
Players in your team games see your display name and the shared board.

We may disclose data if required by law, a court order or a public authority, or to protect our rights or the safety of players.

6. International transfers

Google may process data in the United States and other countries outside the European Economic Area. Google LLC is certified under the EU-US Data Privacy Framework, and transfers are additionally covered by the European Commission's Standard Contractual Clauses included in Google's data processing terms. Our own servers and databases are located in the European Union: the web server and MySQL database in Czechia (Wedos), the multiplayer server in Oracle Cloud's EU region.

7. How long we keep data

Account, profile, game records and leaderboard entries — for as long as your account exists. They are deleted when you delete your account.
After deletion — we keep a single audit entry recording that a deletion happened. It contains a one-way hash of your email address, from which the address cannot be recovered. It is used to detect abuse of repeated account creation.
Multiplayer data (profile, friends, medals, duels, team games, minigame saves) — for as long as your account exists. When you delete your account, your profile, friends, medals, ratings, seats and saves are deleted; past duel records are anonymised (your name and user ID are removed, the result and ratings stay for the other player); team games that had already started keep their shared board for the other players, with your name and user ID removed from it.
Multiplayer server backups — a daily copy of the multiplayer database is kept for 14 days, so deleted data disappears from the backups within 14 days.
Multiplayer server logs — 30 days.
Sign in with Apple token — for as long as your account exists. When you delete your account we revoke it at Apple and delete it.
Moderation records — until the restriction expires or your account is deleted.
Google Drive data — until you delete it or revoke access; the App keeps at most three daily backups and removes older ones.
Data on your device — until you uninstall the App or use the in-app reset.
Emails — as long as needed to handle your request, normally no longer than two years.

8. Children

Cathartic is not directed at children. Creating an account requires you to be at least 15 years old, which is the age of digital consent in Czechia, or older if your country sets a higher age. Younger players may use the App as guests, which involves no collection of personal data by us, with a parent's or guardian's supervision.

If you believe a child under 15 has created an account, write to gamemaster@featurehear.com and we will delete it.

9. Your rights

Under the GDPR you have the right to:

access the personal data we hold about you and receive a copy,
rectify inaccurate data, for example your display name,
erase your data, directly in the App or by email (see Delete your account),
restrict or object to processing based on legitimate interest,
receive your data in a portable format,
withdraw consent at any time, for Drive sync and reminders directly in the App, without affecting processing that took place before withdrawal.

To exercise these rights, email gamemaster@featurehear.com. We reply within 30 days. We may ask you to write from the email address of your account so we can be sure the request is yours.

You may also lodge a complaint with a supervisory authority. In Czechia this is the Úřad pro ochranu osobních údajů (Office for Personal Data Protection). You can instead contact the authority of the EU country where you live.

If you live in California: we do not sell or share personal information as those terms are defined in the CCPA, and we do not use it for cross-context behavioural advertising.

10. Deleting your account

Follow the steps on Delete your account. In short: choose Settings → Profile → Delete account in the App, which deletes everything at once, or email us from your account address and we do it within 30 days. Either way we delete your sign-in account, your profile, your game records, your leaderboard entries and your multiplayer data (duel ratings, friends, medals, team-game seats, minigame saves). Past duel records are anonymised, and shared team-game boards no longer contain your name or user ID. Your data in your own Google Drive and on your device is not touched by us; the deletion page explains how to remove it yourself.

11. Security

All connections between the App, the Study app, the Website and our servers or Google use TLS encryption. Sign-in tokens are stored encrypted on your device. Access to the administration tools is limited to a fixed list of administrator accounts, protected by an additional secret, and every administrative action is logged. No method of storage is completely secure, but we take reasonable measures to protect your data.

12. Website and Study app storage

The Website and the Study app do not use cookies, analytics or advertising trackers. The Study app stores, in your browser only, the Google sign-in token, your Google account ID and email address, your feature-flag cache and your study database, each kept separately per Google account. Signing out removes them. The Study app connects only to Google (sign-in, Drive, Firestore feature flags).

The Website loads the Inter typeface from Google Fonts, which means Google receives your IP address when a page is opened.

13. Changes to this policy

We will update this page when the Service changes in a way that affects your data, and change the date at the top. For significant changes we will also inform you in the App or by email if you have an account.

14. Contact

Štěpán Šrubař, Ostrava, Czechia
gamemaster@featurehear.com