Echo Privacy Policy

Echo is a puzzle game. We keep the data we touch to the minimum needed to run the game and sync your progress across launches. We do not run advertising, we do not use analytics or tracking SDKs, and we do not sell or share your data with data brokers. This policy explains exactly what is stored and why.

What we store

• An anonymous account identifier. When you first open the app we create an anonymous account with Google Firebase Authentication. It is a random identifier. It is not tied to your name, your phone number, or your real email address.
• A device-generated recovery credential. To keep your progress if you reinstall, the app generates a synthetic email/password credential and links it to your anonymous account. This value is generated by the app, is not your real email address, and is stored in your device's secure keychain.
• Your game data. Your puzzle solutions, progress, lineage statistics, in-app settings, and an optional display name you may set (which is private to your account and is not shown to other players) are stored in Google Firestore so your progress is preserved and so your solves can contribute to the shared proof search.
• Abuse-prevention tokens. The app uses Firebase App Check, which produces a device attestation token to confirm requests come from a genuine copy of the app. This guards the backend against abuse.

What we do NOT collect

• No real name, email address, or phone number.
• No location data.
• No contacts, photos, or files.
• No advertising identifiers and no cross-app or cross-site tracking.
• No third-party analytics or crash-reporting SDKs.

How the data is used

The data above is used only to operate the game: to keep you signed in, to preserve and sync your progress, to attribute your solved puzzles within the shared proof search, and to protect the backend from abuse. It is never used for advertising and is never used to track you across other apps or websites.

Where it is stored

Your account and game data are stored on Google Firebase (Firebase Authentication and Cloud Firestore), running on Google Cloud infrastructure. Google processes this data on our behalf as our service provider. See Google's privacy practices at firebase.google.com/support/privacy.

Data retention and deletion

We keep your account and game data for as long as the account exists. You can request deletion of your account and associated data at any time by emailing rostami@outlook.com from within the app or otherwise identifying your account. We will delete it within 30 days. Note that anonymized aggregate contributions to the proof search (counts of cleared cliques) are not personal data and may remain.

Children

Echo is suitable for all ages and is rated 4+. We do not knowingly collect personal information from children. Because the app does not collect a name, email, location, or other personal contact information from anyone, no such information is collected from children either.

Changes to this policy

If this policy changes, we will update this page and the "Last updated" date above.

Contact

Questions about privacy, or requests to delete your data, can be sent to rostami@outlook.com.