If a user installed an app from the app store a month ago, then deleted it at some point and reinstalled it, would its receipt's creation date be the day of original install, or the day of a reinstall?
Also, does this behavior change for a sandboxed app?
Yes, the app's receipt creation date gets reset after an app delete (this is for apps without auto-renewal subscriptions)
I tested this by NSLogging the receipt creation date and testing with an app downloaded from the app store.
Where did they re-install from? icloud? backup? ...?
The receipt is for the original purchase/download. This helps support restoring original purchases. Refreshing the receipt asks the App Store for the latest copy of the receipt/does not create any new transactions.
>Also, does this behavior change for a sandboxed app?
TestFlight apps expire in 30 days, so...
What is it you're trying to do? Flush a sandboxed purchase so you can try anew? If so, it's easiest to just create a new user.
A receipt is created when there is a purchase or when there is a receipt refresh. I would not expect a new receipt for a reinstall but I could be wrong. I could be wrong especially because a receipt is signed with the device's identifierForVendor which can change from one reinstall to another reinstall.
Regrading the sandbox - I believe you get a new receipt each time you reinstall from XCode because each such reinstall is a 'purchase' of the app.
See the correct answer to your needs in the posting above.
Yes, the app's receipt creation date gets reset after an app delete (this is for apps without auto-renewal subscriptions)
I tested this by NSLogging the receipt creation date and testing with an app downloaded from the app store.
