Data controller
Stefano Monticciolo — independent developer, Italy.
Email: [email protected]
Data collected by the app
AstroStackerPro does not collect personal data on external servers. Specifically, the app:
- does not require account creation;
- does not use product analytics or telemetry;
- does not integrate any kind of advertising tracker;
- does not perform automatic uploads of your images;
- does not profile the user;
- does not sell or share data with third parties.
Your photos, capture sessions, settings, location, and every other piece of data the app handles never leave your device. If you have turned on your phone’s backup (iCloud or computer on iPhone, Google backup on Android), the operating system itself includes some of the app’s files in it: you manage that backup with your account, and the author has no access to it.
All data stays on your device. We keep nothing on our servers. Exported photos remain in your Photo Library, under your control.
Permissions
The app may request some system permissions, always in compliance with the operating system’s transparency requirements.
Camera
Required to capture frames and sequences used in astronomical stacking.
Photos / Image library
Used only to read images chosen by the user or to save exported results to the camera roll.
Location (optional)
When granted, location is used for the astronomical planner (Bortle class, Moon times, planets visible in your area), calculated entirely on-device, on both platforms. The app never connects to the internet: cloud detection compares two camera images a few seconds apart, always locally. Your location never leaves your phone, and no server of ours ever receives it.
Motion and orientation
The app locally uses motion and orientation sensors to detect when the phone is on a tripod and to place stars, constellations, the Moon and planets in the viewfinder: gyroscope, accelerometer and magnetometer (the compass, which gives the direction), on both platforms. On iPhone and Android these sensors need no runtime permission. Data stays on the device and is never sent to external servers.
Notifications (optional, Android only)
To show you stacking progress when the phone is in your pocket during a long session, the Android edition asks for the notifications permission. If you allow it, it shows a local notification with the progress of the stack during the session. There is no service that keeps running with the screen off: if you leave the app, the session closes cleanly. If you decline it, the session still works: you only lose the ability to follow it from outside. The iPhone edition does not use notifications.
Differences between the iPhone and Android editions
Both editions share the same philosophy: your data stays on your device. But they aren’t identical. Here’s where they differ.
| Feature | iPhone | Android |
|---|---|---|
| Notifications | No notifications: the iPhone edition does not use notifications. | Notifications permission: a local notification shows the stack progress during the session. No background service. Optional: if you decline it, capture still works. |
Location in photos and on-device logs
Coordinates in exported photos
The app can write location into the EXIF metadata of photos you export. The feature is off by default: it’s turned on only from Settings. Even when active, coordinates are rounded to about 1 km: they identify the observation spot, not the address you shot from.
Session log
The app keeps a local log of sessions: date, duration, capture parameters, outcome, and location rounded to about 1 km. It is never transmitted. On Android it stays in the app’s private folder; on iPhone it is in the app’s documents folder, which is also visible in the Files app. If you have turned on your phone’s backup, it may be included in the backup. You can review it from Settings.
Diagnostic log
To help us understand a malfunction, the app notes the phases of a capture in a local technical file. It contains no personal data and no location. It’s shared only if you tap “Export Log” in Settings: no automatic sending, ever.
Data collected by the website
The astrostackerpro.com site is a static site hosted with standard hosting providers. The site:
- does not use non-essential cookies;
- does not use Google Analytics;
- does not use Meta Pixel or similar tracking pixels;
- does not use marketing automation tools.
The server may record essential technical logs (IP addresses, user-agent, errors) for security and diagnostic purposes. These logs are not used for profiling.
Anonymized visit statistics
To know the aggregate number of site visits we use a fully self-hosted, privacy-by-design statistics system, with no third-party dependency (no Google Analytics, no Plausible, no external service). It works as follows:
- the IP address is turned into an anonymous code via cryptographic hashing (SHA-256) with a random salt that changes every day: after 24 hours it is technically impossible to recover the original IP, even for us;
- the user-agent is reduced to the browser family only (e.g. “Chrome”, “Safari”), with no identifying detail;
- any referrer is reduced to the origin domain only, with no path or parameters;
- the clear-text IP stays in the technical logs for at most one hour, then it is overwritten;
- no cookie, no browser identifier and no tracking JavaScript is installed on your device.
The result is purely aggregate, anonymous statistics (number of visits, most viewed pages, countries, browser type). No data allows identifying or following an individual visitor over time.
Third parties
The app does not send your photos or personal data to third parties: on neither platform does it ever connect to the internet. Any links to app stores or distribution services (such as the App Store, Google Play or TestFlight) redirect to their respective providers, governed by their own privacy notices.
Your rights (GDPR)
Under EU Regulation 2016/679 you have the right to:
- access your data;
- rectify your data;
- erase your data;
- restrict processing;
- object to processing;
- data portability;
- lodge a complaint with the Italian Data Protection Authority.
Since AstroStackerPro does not collect personal data on its own servers, many of these requests may not apply: there is simply no user archive on the controller side to consult or erase. For any clarifications you can write to [email protected].
Policy updates
Any updates to the Privacy Policy will be published on this same page. The date of the last update is shown at the top.
We recommend reviewing this page periodically, especially when new versions of the app are released.
This policy is drafted in Italian, the authoritative language. Translations into other languages are provided for convenience only; in case of discrepancy the Italian version prevails.