Privacy Policy for Stack
Effective date: October 2, 2026
LegendarySZ Apps built the Stack app as a free, ad-supported game with optional in-app purchases. This page explains what information the app collects, why, and how you can delete it.
1. Your Game Account
When you first open Stack, the app creates a guest account for you with Google Firebase Authentication. This account is a random ID; it does not include your name or email. It lets your progress be saved in the cloud and lets you appear on the leaderboard.
You can choose to sign in with Google or with Apple (iPhone only). If you do, Firebase receives your Google or Apple account ID, your email address (with Apple, this can be a private relay address) and your name, if the provider shares it. We use them only to link your progress to your account, so you can keep it on a new phone, and to suggest a leaderboard name. We never send you emails and never share these details.
2. Cloud Save
To keep your progress safe, the app stores this in Google Cloud Firestore under your account ID: your coins, lives, unlocked and selected block skins, best score, number of games played, whether you bought Remove Ads, and your player name.
3. Leaderboard
If your score is high enough to reach the weekly or all-time top 100, everyone who plays Stack can see your entry: your player name, score, selected skin and country. The country comes from your phone's language and region setting, not from GPS. You can change your player name at any time on the RANKS screen. Names with offensive words are not allowed.
4. Analytics and Crash Reports
Stack uses Google Firebase Analytics to learn how the game is played (for example: games started, scores, skins unlocked, shop visits and purchases) and Firebase Crashlytics to receive crash reports (device model, operating system version and the error). This data is tied to a random app instance ID, not to your name. Analytics starts only after the app's consent step has finished.
5. Ads
Stack shows ads to stay free. The ads are provided by Google AdMob. Google AdMob may collect and use information about your device to show ads, measure ad performance and prevent fraud. This can include your device's advertising identifier (Android Advertising ID, or Apple IDFA only if you allow it), your IP address and the approximate location derived from it, basic device information (model, operating system, language) and how you interact with the ads. This information goes directly to Google.
- If you are in the European Economic Area, the United Kingdom or Switzerland, the app asks for your consent before personalized ads are shown. You can change your choice at any time with PRIVACY SETTINGS in the app's Settings.
- On iPhone, the app asks your permission before the advertising identifier (IDFA) is used. If you do not allow it, you still see ads, but they are less personalized. You can change this in Settings > Privacy & Security > Tracking.
- On Android, you can reset or delete your advertising ID, or opt out of personalized ads, in your device settings.
Buying Remove Ads turns off banner and full-screen ads. Optional reward videos stay available.
6. In-App Purchases
Purchases of lives, coins and Remove Ads are one-time purchases (there are no subscriptions). Payment is handled entirely by Apple (App Store) or Google (Google Play); we never see your card or payment details. The app only receives a confirmation of what you bought, so it can add it to your game.
7. Third-Party Services
These services process data for Stack under their own privacy policies:
- Google Firebase (Authentication, Cloud Firestore, Analytics, Crashlytics): https://firebase.google.com/support/privacy
- Google AdMob: https://policies.google.com/privacy and https://policies.google.com/technologies/partner-sites
- Sign in with Google: https://policies.google.com/privacy
- Sign in with Apple: https://www.apple.com/legal/privacy/
8. Information Stored on Your Device
The app also keeps a small save file on your device with your progress and settings (sound, vibration). Uninstalling the app removes it.
9. Deleting Your Account and Data
You can delete your account inside the app at any time: open Settings (the gear on the home screen) and tap DELETE ACCOUNT. This permanently deletes your cloud save, removes you from the leaderboards and deletes your sign-in account. Your progress on the phone then starts again from zero. If you bought Remove Ads, you can get it back with RESTORE PURCHASES, because purchases belong to your Apple or Google account.
If you cannot open the app, email us at legendaryszapps@gmail.com from any address with the subject "Delete my Stack account" and your player name. We will delete your account and data within 30 days and tell you when it is done.
Analytics and crash data are kept by Google for up to 14 months and are not linked to your name. To manage ad data, reset your advertising ID or visit https://myadcenter.google.com.
10. Children's Privacy
Stack is not directed at children under 13. We do not knowingly collect personal information from children under 13. If you believe a child has used the app and given us personal information, contact us and we will delete it.
11. Security
All data sent between the app and Google's services uses encrypted connections (HTTPS). Cloud data is protected by security rules, so each player can read and change only their own save.
12. Changes to This Privacy Policy
We may update this Privacy Policy from time to time. We will post the new version on this page, with a new effective date.
13. Contact Us
If you have any questions about this Privacy Policy, contact us at: legendaryszapps@gmail.com