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Hi, We would like to submit a paid application (on the Mac App Store) and we would like to know if it would be possible to identify a unique user (not across apps but only for this app) via the receipt. I've been thoroughly reading the Apple documentation to verify a receipt (https://developer.apple.com/documentation/AppStoreReceipts) and found that there is a field original_transaction_id that could serve for this purpose. There are two places where this field can be found, but both are indicated to be present only for in-app purchases. The question in general is, is there any way to obtain a transaction_id or original_transaction_id from a paid app? To be more specific on the fields we're looking at, on the verifyReceipt response: responseBody.Latest_receipt_info.original_transaction_id: Latest_receipt_info should only include non-finished in-app transactions, would this include the app transaction itself? responseBody.Receipt.In_app.original_transaction_id: the receipt should always be present, but it carries no transaction_id or anything similar, would the purchase of the app itself be included inside the In_app array (along all actual in-app purchases)? Thank you for your time.