iOS App Purchase Date

Question

I'm trying a new market strategy so I'm gonna put my 0,79€ App now for free, with an in-App purchase that unlock ALL the contents. I also do not want to betray the users which already has bought it, so I thought to implement a check where who already have bought the App, don't need to purchase the in-App payment to unlock all.

My problem is... can I check when the App has been purchased? Or maybe there is a simple way?

Answer 1

You can't do this with any certainty, since there is no way to check if the user bought the app because there is no way to ask the OS about the install/purchase date.

As suggested, you could save it in the NSUserDefaults, but if the user deletes the app, this information is lost.

One could save it in the keychain, which is not cleared if you delete the app, but the problem is still there, because if the iOS device gets restored, these settings could be lost.

Answer 2

just to update this, it IS possible. Take a look at the answer to this question -- one of the fields in the receipt is "original purchase date"

A complete solution to LOCALLY validate an in-app receipts and bundle receipts on iOS 7