Contact support
Email support@astrostacker.app. Include your iPhone or iPad model, the iOS or iPadOS version, the app version (shown at the bottom of Settings), how many frames you stacked, and the exact error message or a screenshot.
Common problems
“Not Enough Usable Stars”. The app couldn’t find enough clear stars to line your frames up. Read how to fix it.
“Color Format Mismatch”. Some frames are colour and some are greyscale. Stack frames from one camera with one colour setting.
The stack stops partway through. Test with fewer frames first, close other apps and free up storage, then build up the set. A failed or cancelled stack doesn’t use one of your free stacks.
Moon or planet photos won’t stack. Stacking aligns on stars, so these aren’t supported yet. Planet Lab is coming soon.
Purchases and subscriptions
Purchases go through Apple. To restore Pro on a new device, open the app’s Pro screen and tap Restore Purchase. To cancel or change a subscription, or to ask for a refund, use your Apple Account’s subscription settings or Apple’s Report a Problem page.
Learn the workflow
Get the best results, choose a stack mode, or browse all guides. See also the privacy policy and terms of use.