Privacy Policy

This policy describes what information the Mahjong app ("the app") collects, how it is used, and what you can do about it. The short version: we collect what the game needs to work, plus a small amount of analytics about how the app is used. We don't run ads, we don't track you across other apps, and we never sell your data.

Information we collect

• Account identifier. When you sign in, we create a game account tied to an identifier from Sign in with Apple or a per-install device identifier. We do not receive your Apple ID password. If you choose to share your name or email via Sign in with Apple, it is used only to label your account.
• Profile. Your display name, chosen avatar, and in-app preferences (e.g. sounds, haptics, hints).
• Gameplay records. Match results and history, in-game actions needed to run and audit fair games, experience points, achievements, and daily-reward streaks.
• Friends. Your friend code and friend list, if you use the friends feature.
• Product analytics. A fixed set of usage events. From the app: that it was opened, that sign-in started, which onboarding step you reached, whether you finished or skipped the tutorial, and which screen you are on. From our game servers: that you signed up or signed in, that a match started, completed or was abandoned, and that a private room was created or joined. Match events carry metadata about the game (mode, how long it ran, the result and its faan, how many humans and bots were seated), never the contents of your hand or your tiles.

We do not collect your contacts, precise location, photos, advertising identifiers, or any browsing data. The app runs no advertising, and nothing in it tracks you across other apps or websites.

Analytics, in detail

We use PostHog as our processor for product analytics, on their United States infrastructure. It is set up deliberately narrowly:

• Pseudonymous. Events are identified by an analytics id the SDK generates for your install, and, once you sign in, by the opaque account id our own servers issue. Your display name, email, and Apple identifier are never sent, and neither are the contents of your hand.
• No automatic capture. There is no autocapture: every event is one we added by hand, and the list above is the whole of it. Like any analytics tool, each event does carry standard technical properties such as app version, device type, and the IP address the request came from, and PostHog derives a coarse (city-level) location from that IP so we can choose server regions. Precise location is never collected.
• No session recording. We do not record your screen, replay your sessions, or capture what you type.
• No advertising use. No IDFA, no ad networks, no cross-app or cross-site tracking, and no sale of the data.
• Also used for feature configuration. The same service delivers remote settings, for example temporarily turning a feature off for maintenance.
• Cleared when you leave. Signing out or deleting your account resets the identifier on your device, so later activity is not tied back to the account that left.

How we use it

Solely to operate the game: running matches on our servers, preventing cheating (games are validated server-side), showing your profile and history to you and the players you play with, and maintaining social features you opt into.

Where it lives

Game data is stored on our game servers hosted in the United States. Data is transmitted over encrypted connections. A session token and small caches are stored on your device.

Sharing

We do not sell or rent your personal information, and we do not share it for advertising. We share it only with the service providers that make the game run, and only so they can run it: the hosting infrastructure behind our game servers, and PostHog for the analytics and feature configuration described above. We will also disclose information if the law requires it. Other players can see your display name, avatar, level, and shared match results — never your account identifier or email.

Retention and deletion

You can delete your account at any time in the app underSettings → Account → Delete Account. Your account is hidden immediately, and signing back in within 30 days cancels the deletion. After that we hard-delete your profile, progression and stats, and we anonymise your entries in the shared match log: those entries are interleaved with three other players' matches, so removing them outright would corrupt other players' history. Deleting your account also disconnects your analytics profile, so the pseudonymous id stops being associated with any account.

Match history and the match log are kept to preserve game history and integrity for everyone who played. Operational logs are kept about 30 days. Analytics are retained in PostHog under our project's retention settings and used in aggregate.

Children

The app is not directed at children under 13, and we do not knowingly collect personal information from them. The game contains no real-money wagering; scores and points have no monetary value.

Changes

If this policy changes materially, we will update this page and note the new effective date above.

Contact

Questions or requests about your data: mart0605@gmail.com