1. Who operates Astro Stacker
Astro Stacker is the operator of this website and the Astro Stacker iOS app. For privacy questions or requests, email privacy@astrostacker.app. General support is available at support@astrostacker.app.
2. Information used by the website
We use Vercel Web Analytics to understand page views, referral sources, device types, browsers, approximate country or city, and clicks on our App Store buttons. Vercel Web Analytics is designed to provide aggregated, anonymous statistics without third-party analytics cookies or persistent cross-site identifiers.
Our custom download event contains only the button placement, the destination “app_store”, and the public page path. We do not intentionally send names, email addresses, photo contents, precise location, or payment information with analytics events.
3. Photos and app processing
Astro Stacker processes the photos you choose for stacking on your device. The core import, alignment, calibration, stacking, enhancement, and export workflow does not require your images to be uploaded to Astro Stacker servers. Your Photos and Files permissions are used only when you ask the app to import or save content through Apple’s system interfaces.
If you choose to sign in, newly completed stacked result images are privately backed up to our Supabase storage. This is optional, helps recover a result when its local copy is no longer available, and does not make the image public. Source frames are not uploaded by this backup feature.
4. App Store purchases
Downloads, subscriptions, lifetime purchases, billing, refunds, and purchase history are handled by Apple under your Apple Account and Apple’s privacy terms. RevenueCat helps us validate purchase entitlements and restore subscription access. We do not receive your full payment-card details. Apple and RevenueCat may provide transaction status needed to unlock or restore the features you purchased.
5. Accounts, syncing and diagnostics
You can use the Free plan without creating an account. If you choose to create an account, sign in, purchase Pro, or sync your history, we use the account details you provide—such as your email address or Sign in with Apple identifier—to authenticate you, restore access, keep eligible history available across your devices, and associate private result backups with your account.
The app may send limited operational information about stacking attempts, performance, app version, device characteristics, and errors so we can diagnose reliability problems and improve the product. This operational information does not include the contents of the photos you import, finished images you export, or GPS location metadata from images.
6. Messages you send us
If you send feedback in the app or email support or privacy, we receive the information you include, such as your message, category, email address where provided, app version, device model, operating system version, and any attachments. In-app feedback from a signed-in user is linked to that account. We use it to answer your request, investigate a problem, protect the service, or meet legal obligations. Please do not attach private photographs or sensitive information unless it is necessary for your request.
7. Legal basis and retention
Where UK data-protection law applies, we rely on legitimate interests to operate, secure, measure, and improve the website; performance of a contract to provide purchased app features; and legal obligations where applicable. Anonymous analytics are retained according to the settings and retention periods available in our Vercel account. Support messages are kept only as long as reasonably needed to resolve the request, maintain necessary records, or comply with law. Account, purchase-entitlement, synced-history, diagnostic records, and private result backups are retained only as long as reasonably necessary to provide, secure, and improve the features you use or to meet legal obligations. You can delete your account in the app under Settings > Profile > Delete Account. This immediately disables the account and removes it from the app. Account data and private result backups are retained in a deleted state until permanently removed by our team; local files remain on your device unless you remove them yourself.
8. Service providers and international processing
We use Vercel to host and measure this website, Apple to distribute the app and process purchases, Supabase to support account authentication, database features, diagnostics and private result backup storage, and RevenueCat to support subscription status. These providers may process information in countries outside your own under their contractual and legal safeguards. Their independent notices explain their processing in more detail.
9. Your rights
Depending on where you live, you may have rights to access, correct, erase, restrict, port, or object to the use of your personal information, and to complain to a data-protection authority. Email privacy@astrostacker.app to make a request. In the UK, you may also contact the Information Commissioner’s Office.
10. Children and changes
Astro Stacker is not directed to children under 13, and we do not knowingly collect their personal information through this website. We may update this policy when the app, website, providers, or law changes. The date at the top shows the latest revision.