Privacy, in plain terms

Mahjong Night is a free game by Dayplay Games, a brand of Winter Watermelon. It works without an account. Leaderboards and playing at a table with friends online are optional and need a Dayplay Games player name.

Your records stay here

This browser stores your sound, motion, hint and chat settings, the hands you have played and won against each computer level, your best result at today's table for each of the last 30 days, whether you finished the lesson hand and whether you have seen the first-visit tutorial. None of this is sent anywhere unless you pick a player name (below), and it does not sync to other devices. If browser storage is blocked, settings and records last only on the current page.

Leaderboards (optional)

With a Dayplay Games player name, a finished game at today's table or a four-hand game against the Pro computers sends its points to that leaderboard, and the first time you pick a name your best results already on this device are sent once. The server keeps one best result per player per board, with the day for the daily board. Other games against the computer and tables with friends do not post scores. Without a name nothing is sent. See the Dayplay Games privacy page for names, passwords and deleting your scores.

Playing with friends online (optional)

To sit at a table with friends you need a Dayplay Games player name (see the Dayplay Games privacy page). The host opens a table and sends an invite link; anyone with the link can take an empty seat until the game starts, and computer players fill the seats left over. Each table runs on our server, which deals the tiles and only ever sends you your own tiles and what everyone can see on the table. A table and everything about it is deleted when it closes. During a game this tab keeps the table key, so a reload can sit you back down; it goes when you leave the table or close the tab. Online play talks to our server whatever your analytics choice, because a table cannot run without it. The others at the table see your name, the tiles you pass, throw and expose, and the fixed quick-chat phrases you pick; there is no free text between players.

Hourly counters of tables opened are keyed by a one-way hash, not your name, and deleted after two days.

An invite link carries a random table key. The game takes it out of the address bar as soon as the page opens, but your browser history may still list the full link. The key is not sent to analytics.

How play counts work

When product analytics are allowed, we also use Google Analytics, based in the United States, to measure visits and named product actions. It uses first-party browser and session cookies, processes connection information such as IP addresses to provide the service, and receives fixed page routes, approved campaign labels and the referring site hostname. We do not send form contents, uploaded files, email addresses or private workspace addresses. Advertising signals and personalization are disabled. The same regional consent, browser privacy signals and turn-off control apply to both analytics services; turning analytics off stops Google collection and removes its cookies. Google analytics event data is retained for up to 14 months. Anonymous totals are not sent to Google.

Outside the EU/EEA, UK and Switzerland, product analytics (PostHog, based in the United States) are on by default to help us improve the game; use the button above to turn them off at any time. Global Privacy Control and Do Not Track are honored automatically and always keep analytics off with no prompt, even if you had allowed analytics on this browser before.

In the EU/EEA, UK and Switzerland, and wherever we cannot tell, we ask first with a small floating card on the game page. Until you allow it, PostHog is not loaded; the page may still send one anonymous visit count with no player or browser ID.

If analytics are on, PostHog receives a random browser ID, session ID, which screen you opened (the menu, or a game with its mode or computer level, never a page address) and fixed milestones: game start, game completed (won, lost or a draw, a points range and the number of hands you won), game left early and full-screen use. Events include approximate country from the service edge when available; event IP is masked. We do not send your tiles, the tiles you pick, key presses, arbitrary link parameters, typed text or raw error messages. There is no session recording, no device fingerprinting, no advertising and no sale of data.

Hosting and network providers receive the connection information needed to serve requests, including your IP address, in their own logs; that is separate from the controls above.

Change your choice

Use the button under “How play counts work” above. Turning analytics off immediately removes the stored measurement ID, attribution and activation record from this browser; previously delivered events remain. Your records are separate and stay intact either way. Embedded play keeps no analytics at all.

Questions

Write to hello@dayplaygames.com with a privacy question. Please avoid sensitive information.