Chronophoto ("Chronophoto," "we," "us," or "our") is a mobile game where you guess the year a real historical photo was taken. This policy explains what information the Chronophoto app collects, how it's used, and the choices you have. It applies to the Chronophoto app on both iOS and Android.
The short version: Chronophoto doesn't require an account, doesn't ask for your name or email, and doesn't collect your location, photos, or contacts. The app shows ads through Google AdMob and its partners (which collect some device data to do that, and may personalize ads only if you allow it), uses TelemetryDeck for anonymous usage analytics, and your scores/streaks/badges are stored on your own device, and can optionally sync across your own devices through your Apple iCloud account (iOS) or your Google Drive account (Android), which we never see.
Chronophoto has no accounts of its own, and you can play without signing in to anything. On Android, you may optionally sign in with your existing Google account to sync your progress to your own Google Drive (see Section 2.3); this is entirely optional, we never receive your Google password, and we do not collect your name or email address for our own use. We do not ask for your phone number or payment information. The app does not request access to your camera, photo library, contacts, or your precise or approximate location, and it does not use any of these on your device.
Chronophoto is free and supported by ads served through Google AdMob (banner, occasional interstitial, and an optional rewarded ad if you choose to continue in Survival mode). To deliver and measure ads, Google AdMob and its partners may collect device and advertising identifiers, general device information, and approximate usage data, in accordance with Apple's and Google's advertising rules. Some of these ads are served by mediation partners that bid through AdMob: Unity Ads (privacy policy) and Liftoff Monetize (privacy policy).
On iOS, the app asks for your permission through Apple's App Tracking Transparency prompt, introduced by a short Google explainer. If you allow tracking, Google AdMob and its mediation partners may use your device's advertising identifier (IDFA) to personalize and measure ads. If you don't, ads are still shown, but they aren't based on tracking you across other companies' apps and websites, and the app works the same either way.
For users in the United Kingdom, the European Economic Area, and Switzerland, the iOS app also shows a Google consent message (Google's User Messaging Platform) before any ads are requested, and that consent decides whether ads may be personalized. In US states with privacy laws, you can opt out of the sale or sharing of your personal information for targeted advertising. Both are available at any time from the gear icon on the home screen → Privacy settings, and Chronophoto passes your choice on to its mediation partners.
You can review how Google handles this data at Google's Privacy Policy and AdMob's data disclosure. You can limit ad-related tracking at any time in iOS Settings → Privacy & Security → Tracking and Settings → Privacy & Security → Apple Advertising. On Android, you can reset or delete your advertising ID in Settings → Google → Ads.
Chronophoto uses TelemetryDeck, a privacy-focused analytics service, to understand how the app is used so we can improve it. When you use the app, it sends short usage events to TelemetryDeck, such as: a session starting; a game being completed or abandoned (with the game mode, and for abandoned games the round reached); a daily challenge completed (with your streak length); a badge being unlocked; a rewarded ad being watched; a streak rescue being offered, completed, declined, or unavailable (with the reason); a party code being created or opened; and a daily reminder notification being opened.
Each event is tied to a random identifier that the app generates on your device the first time it runs and then stores locally. That identifier is hashed (SHA-256) on your device before it is sent, so it is not your name, email, advertising ID, or any account identifier, and it cannot be used to identify you. According to TelemetryDeck, user identifiers are hashed a second time on its servers with its own salt, so that neither TelemetryDeck nor we can rebuild the original identifier. The analytics events do not include your name, email, precise or approximate location, contacts, or photos. Analytics are not used for advertising or to track you across other apps and websites. Deleting the app removes the identifier from your device.
See TelemetryDeck's Privacy Policy and its explanation of how anonymization works.
Your scores, streaks, badges, and daily-challenge history are stored locally on your device. If you have iCloud enabled, this data may also sync through Apple's iCloud Key-Value Storage so your progress carries over across your own devices signed into the same Apple ID. This sync is provided and controlled entirely by Apple under Apple's Privacy Policy. Chronophoto's developer does not receive, see, or store this data on any server.
On Android, this same progress data can optionally sync through Google Drive instead. If you choose to sign in with your Google account, Chronophoto requests only the limited drive.appdata permission, which lets it read and write a single hidden, app-private folder in your own Google Drive; it cannot see, access, or modify any of your other Drive files. Your scores, streaks, and badges are stored there so your progress carries across your own Android devices. This data lives in your own Google account under Google's Privacy Policy; Chronophoto's developer does not receive, see, or store it on any server. Signing in is entirely optional, and the game works fully without it.
If you allow notifications, Chronophoto schedules reminders locally on your device (for example, a nudge before your daily streak resets). These reminders are generated and delivered entirely on-device, and nothing about your streak or activity is sent to us or any third party to create them. You can disable notifications anytime in iOS Settings → Notifications → Chronophoto.
The historical photos you're shown are delivered through a content delivery network (Amazon CloudFront). To fetch them, the app requests a temporary, anonymous access credential (via AWS Cognito) used only to gate access to image files and apply basic rate-limiting. This credential is not tied to your name, account, or any other identifying information about you.
Party mode lets you share a game code or link with friends. That code is generated and shared directly from your device (for example, through the iOS share sheet) — Chronophoto does not store party codes or who you shared them with on any server.
Like most apps, Chronophoto may use basic, non-identifying device and app information (such as OS version, app version, and device model) to keep the app running correctly and to diagnose crashes or bugs. This is not linked to your identity.
We do not sell your personal information for money, and we do not use any of the above to build an advertising profile of you ourselves. Sharing device and advertising data with Google AdMob and its mediation partners so they can show you targeted ads may count as a "sale" or "sharing" of personal information under some US state laws. You can opt out at any time from the gear icon on the home screen → Privacy settings.
| Service | Purpose | Learn more |
|---|---|---|
| Google AdMob | Ad serving | Google Privacy Policy |
| Unity Ads | Ad serving (mediation partner) | Unity Privacy Policy |
| Liftoff Monetize | Ad serving (mediation partner) | Liftoff Privacy Policy |
| TelemetryDeck | Anonymous product analytics (anonymized usage events and a hashed, randomly generated install ID) | TelemetryDeck Privacy Policy |
| Apple iCloud (iOS) | Cross-device progress sync (optional, on-device controlled) | Apple Privacy Policy |
| Google Drive & Google Sign-In (Android) | Optional cross-device progress sync to a hidden, app-private folder in your own Google Drive | Google Privacy Policy |
| Amazon Web Services | Image hosting & delivery infrastructure | AWS Privacy Notice |
Data stored locally on your device (scores, streaks, badges) remains there until you delete the app or clear its data. Data synced to your own iCloud (iOS) or Google Drive (Android) is retained according to your own iCloud or Google account settings, and you can remove it there at any time. We do not operate servers that store personal information about you, so we have nothing to retain or delete on our end beyond what's described above.
Chronophoto is not directed at children under 13, and we do not knowingly collect personal information from children under 13. If you believe a child has provided us with personal information, contact us at the email below and we will address it.
If you're in the EU/UK, California, or another region with data protection laws, you may have additional rights (such as access, deletion, or objection requests). Because Chronophoto collects minimal information that is not tied to your identity, many of these requests won't apply — but you're welcome to contact us with any question or request and we'll respond.
We rely on reputable providers (Apple, Google, Amazon Web Services) that maintain their own security standards for the services described above. No method of electronic storage or transmission is 100% secure, and we can't guarantee absolute security.
Chronophoto's infrastructure providers (including AWS) may process data in the United States and other countries. By using the app, you understand your information may be processed outside your country of residence.
We may update this policy as the app changes — for example, if we add new features or change the services we use. We'll update the effective date above, and for material changes, we'll provide reasonable notice within the app or on this page.
Questions, requests, or concerns about this policy or your data? Reach us at support@chronophoto.app.