1. Introduction
This app is a game where photos you take become silhouette pieces you stack. Photos are the raw material of the game, so we describe how they are handled as concretely as we can.
When you play alone, the photos you take never leave your device (unless you share them yourself). A photo is sent only in online matches, where your piece has to appear on your opponent's screen (sections 3–5). In "Challenge a tower" mode, only the outline shape of your pieces is shared, never the photo (section 2).
2. Information we collect
- Photos taken inside the game: cut out on your device and turned into pieces. If no subject can be found in a photo, the uncut photo itself becomes a rectangular piece. Photos leave your device only in online matches, or when you share them yourself (sections 3 and 4).
- Piece outlines ("Challenge a tower" mode only): when you play this mode, the outline of each piece (up to 64 points per piece, with its position, rotation and size — no image) is saved to our online record board together with your user ID, player name and score, and is shown to other players. Regular solo play ("Play Solo") does not upload or share your photos or piece outlines (play statistics are saved as described below).
- Player name: the display name you enter. Shown to opponents in online matches and on leaderboards and record boards, and also saved in the cloud with the play statistics below.
- Play statistics and game progress: matches played, best records, coin balance, items you own, and similar. For every player, including guests and including solo play, these are saved in the cloud (Firebase Realtime Database) under your in-app user ID. If you link an account, they carry over to a new device.
- Account-linking information (only if you link an Apple or Google account): the email address provided by that service (if you hide your email with Sign in with Apple, the relay address Apple provides) is kept in Firebase Authentication as part of your sign-in information and is shown on the Settings screen. For a Google account, its display name is also kept. Your user ID on the linked service and, for a Google account, the profile picture URL (if Google provides one; the app does not use it) are also kept in Firebase Authentication as part of your sign-in information. A name provided by Apple (only if you choose to share it) is stored only on your device and is not sent to our servers. To detect a sign-in on another device, a random per-device ID generated by the app is also saved in the cloud.
- Usage statistics: events such as app launches and matches, sent to Google Analytics with a random ID generated by the app, your in-app user ID, and your language and region settings (not your name or contact details); and the information required to serve ads (Google AdMob), including the advertising identifier (IDFA) if you allow tracking.
- Reports: when you report a player from inside the app, the user IDs of the reporting and reported players, the reported player's player name, the reason and the time are saved in our access-restricted database (section 9).
- Challenge link records (only when a challenge link is created as you share a result): your user ID, player name, the outlines of that tower's pieces (no images), its height, piece count, the app's display language and the time of creation are stored in the cloud. Anyone with the link can see the player name, tower outline, height and piece count on a web page and in the app.
- Game Center scores (iOS only, when you are signed in to Game Center): your best height and most pieces are sent to Apple's Game Center leaderboards. How they are shown is governed by your Apple settings and Apple's privacy policy.
- Invitation records (only if you use a friend's invite code): your user ID, the inviting player's invite code, the time, and whether you have finished your first match are saved in the cloud. The inviting player's app reads this record to award coins.
The app may introduce other apps by the same developer. Tapping one opens that app's page on the App Store or Google Play. The store only receives a tag showing which spot in the app the visit came from; none of your personal information is passed on (how often these are shown and tapped is recorded as part of the usage statistics above).
We do not collect your address, phone number, date of birth, or precise (GPS) location, and we do not collect your name except for the display name received when you link an account (see above). Payment information is handled by Apple and never reaches us.
3. Photos that may show faces (face data)
This app does not perform face detection or face recognition. It does not collect, derive or store facial landmarks, face geometry, face templates, depth data or any other biometric data, and it does not use Face ID. However, the photos you take may show your face or other people's faces. Those photos are handled as follows.
- Processing: each photo is cut out on your device by an image model built into the app. The model only separates the subject (a person, a pet or an object) from the background; it does not detect faces or identify anyone.
- Solo play: photos never leave your device (unless you share them yourself). In "Challenge a tower" mode, only piece outlines (no image) are shared (section 2).
- Online matches: each piece image (normally at most 512 pixels on its longer side, or at most 1024 pixels in the rare case that the reduction step fails) is (1) sent to your opponent, encrypted with a key unique to that match, and (2) stored in our moderation archive so that we can act on reports (sections 4 and 5).
- Who can see them: your opponent during the match, and us, only when a report or a technical investigation requires it. However, from the app's result screen your opponent can save the result image or a replay video of the match, which may show your pieces, on their own device and share it through other apps.
- Sharing: never sold or provided to third parties, and never used for advertising or to train machine-learning or AI models. Neither the app nor our server-side processing sends them to any third-party AI service (for a past exception, see section 7). Google LLC stores and relays them on our behalf (section 7).
- Where they are stored: Google Cloud / Firebase — Firebase Realtime Database (Singapore) and Firebase Storage (Taiwan); Cloud Functions (Iowa, United States) receive archive uploads and run the scheduled deletions (section 7).
- How long: the app deletes relayed copies from the database when the piece is placed and when the match ends, and from Firebase Storage when the match ends. Copies left behind, for example when the app closes during a match, are also deleted by a server-side rule and a daily job (section 9). Archive copies are deleted automatically once they are more than 30 days old, except as described in section 5.
- Deletion: deleting your account in the app's Settings also deletes archive copies, except as described in section 5. You can also contact us (section 10).
4. How photos are handled in online matches
In an online match your photo is sent because your piece has to appear on your opponent's screen. Here is what happens.
- The copy sent to your opponent is encrypted with a key unique to that one match. The key is kept with the match room in our Firebase database, and our access rules and app logic allow only the two players in that match to read it.
- A separate copy is kept for handling reports. The app sends the same piece image over an encrypted (HTTPS) connection to our server (Google Cloud Functions). The server immediately encrypts it with a key that only we hold and stores it with your user ID, player name and match room code. See section 5.
- Inappropriate images are handled through reports. There is no automated screening before an image is sent. If you are shown something objectionable you can report it from inside the app; we review it and take action, such as excluding the reported player from random matchmaking (a ban).
- Result images and replay videos: from the result screen, each player can save the result image or a replay video of the match on their own device and share it through other apps. In an online match, the image or video can include the opponent's pieces.
5. About retention for handling reports
In online matches your piece is shown to people you do not know. That means we sometimes receive reports along the lines of "I was shown something offensive" — and if we cannot look at what was reported, we can neither act on it nor prevent it happening again. Piece images created to be sent to an opponent in online matches are retained for that purpose and no other.
Specifically:
- Only piece images created to be sent to an opponent in an online match are retained (including any that failed to send and had to be retaken).
- They remain encrypted while stored. The accompanying record (user ID, player name, room code, time) is kept in our access-restricted database.
- They are viewed only when a report or a technical investigation requires it.
- They are deleted automatically by a daily job once they are more than 30 days old (in practice within 32 days of being sent).
- They are never used for advertising, for training machine-learning models, or for any other purpose, and are never provided or sold to third parties.
Deleting your account deletes these images too. The exception is when there is any record of a report about you (including reports that have already been dealt with): those images are then not deleted and are kept until they are deleted automatically as described above. If someone could stop a report from being looked at simply by deleting their account, we could not protect the person who reported it. In addition, if a specific image is needed for an investigation of a report, we may preserve it until that investigation is finished (while preserved, it is exempt from the automatic deletion described above), and then delete it.
6. Purposes of use
- Providing and maintaining the app (image sync during matches, saving records and play statistics, sign-in and account management)
- Keeping play safe (responding to reports, reviewing reported images, excluding abusive players from random matchmaking)
- Statistical analysis to improve the app (without your name or contact details)
- Serving advertisements (section 8)
7. Disclosure to third parties, processors and storage locations
We do not provide collected information to third parties except with your consent, where required by law (for example a formal request from a court or law-enforcement agency), or where necessary to protect a person's life, body, or property.
We use the following processors. Neither this app nor our server-side processing sends personal data, including photos, to any third-party AI service. In addition, from July 7, 2026 through August 11, 2026, a server function of ours sent some online-match piece images to Google Cloud Vision API for automated inappropriate-content screening. We no longer do this.
- Google LLC (Firebase Authentication / Realtime Database / Storage / Cloud Functions): sign-in, match synchronisation, relay of encrypted images, saving play statistics, and the moderation archive. Storage and processing locations: Realtime Database — Singapore (asia-southeast1); Storage — Taiwan (asia-east1); Cloud Functions — Iowa, United States (us-central1), except random-match pairing, which runs in Singapore (asia-southeast1). Firebase Authentication (sign-in information, including the email address and display name received when you link an account) is a service for which we do not specify a location; it may be processed in Google facilities, including in the United States.
- Google LLC (Google Analytics / AdMob / User Messaging Platform): usage analysis, ad delivery and ad consent. They do not receive photos. These are also services for which we do not specify a location; they may be processed in Google facilities, including in the United States.
- Apple Inc.: app distribution, in-app purchase processing, Sign in with Apple, Game Center leaderboards (iOS).
8. Advertising, tracking and consent
This app displays advertisements (Google AdMob). On iOS, the App Tracking Transparency prompt asks whether you allow tracking. If you are in the European Economic Area, the United Kingdom or Switzerland (as determined by Google from your device's network location), Google's consent message (User Messaging Platform) is shown before that prompt and asks whether your data may be used for advertising. If, in that message, you do not consent to storing or accessing information on your device, or to the use of your data for personalised advertising, we treat this as having already declined tracking and do not show the App Tracking Transparency prompt (in that case the advertising identifier (IDFA) is not available either). You can change your choice in that message under “Ad privacy settings” in the app's Settings screen (this item appears when Google's consent service determines that it is required). On first launch, ads are requested only after these choices have been made. On later launches, ads are requested based on your previous choices, and if your consent needs to be collected again (for example, when it has expired or your device is newly determined to be in the European Economic Area, the United Kingdom or Switzerland), the consent message is shown during that launch. Declining the tracking prompt only means ads are not personalised to you; no app feature is restricted. If you decline, iOS does not make the advertising identifier (IDFA) available to this app, so it is not shared with the ad provider either. Ads can be removed via an in-app purchase.
9. Retention periods
- Images relayed during a match (encrypted) and match room data, including the match key: the app deletes images from the database when the piece is placed and when the match ends, copies in Firebase Storage when the match ends, and the match room when a player leaves after the match. If the app could not delete them, copies in Firebase Storage are deleted by a server-side rule once they are more than one day old (normally within two days of upload), and match rooms left behind, for example after a lost connection or a force-quit, are deleted together with their key and images by a daily automated job (rooms whose last activity is more than 24 hours old; normally within 48 hours of the last activity). Leftover fragments of finished matches are deleted by the same job.
- Images retained for handling reports (section 5): deleted automatically once they are more than 30 days old (within 32 days), except as described in section 5.
- Piece outlines on the record board, play statistics, invitation records and account information (including the email address and display name received when you link an account): kept until you delete your account, which you can do from the in-app Settings screen.
- Challenge link records: deleted automatically 180 days after creation, and earlier together with your account if you delete it.
- Report records and ban records (exclusion from random matchmaking): kept without a fixed time limit to keep play safe. Records of reports about you and any ban record remain even if you delete your account (records of reports you made are deleted).
10. Your rights
To request disclosure, correction, or deletion of your data, contact com.yy.app@gmail.com. You can also delete your account from the in-app settings screen.
11. Children's privacy
This app is rated for ages 4 and up. If you are under 13, please use it with a guardian's consent. Because online matches show your photo to people you do not know, we ask that a guardian review this before a child plays.
12. Camera access
The app requests camera access in order to create game pieces. If you decline (or the camera cannot be used), you cannot start a game, whether you play alone or in an online match. However, if you turn on “Streamer Mode” in the app's Settings (when this item is shown), you can play without the camera, using the included character pieces. In online matches, your opponent sees these pieces. If the camera stops working during a game, that game continues with the included character pieces. You can change the permission at any time in your device settings. Photos are processed on your device (see section 3).
13. Changes to this policy
We may change this policy when we consider it necessary. Significant changes will be announced in the app or on the support site.
14. Contact
Questions about this policy: com.yy.app@gmail.com