Short reminders for in-app purchases and receipt validation.

Load the receipt that’s stored in the app bundle.

Verify the receipt using the multi-step process using a library. Verify the in-app purchases in the receipt.

https://developer.apple.com/library/content/documentation/NetworkingInternet/Conceptual/StoreKitGuide/Introduction.html#//apple_ref/doc/uid/TP40008267

https://developer.apple.com/library/content/releasenotes/General/ValidateAppStoreReceipt/Introduction.html#//apple_ref/doc/uid/TP40010573

https://github.com/Cocoanetics/Kvitto

https://github.com/crashoverride777/SwiftyReceiptValidator