My solution was to query all built-in ethernet interfaces—in technical terms, kIOBuiltin devices of kIOEthernetInterfaceClass—and attempt to validate each interface’s MAC address with the App Store receipt until a match was found. This might be the same technique suggested by Paulo Andrade, but that blog post contains no sample code.

Quelle: Mac App Store receipt validation revisited, via Receipt Validation With All the Ethernet Interfaces.

Was ist denn überhaupt ein App Store Receipt?

An App Store receipt provides a record of the sale of an app and any purchases the person makes within the app. You can authenticate purchased content by adding receipt validation code to your app or server. Receipt validation requires an understanding of secure coding techniques to employ a solution that’s secure and unique to your app.

Quelle: Choosing a receipt validation technique.

Spannend. Wieder etwas gelernt. Doch was passiert, wenn ich mein Gerät wechsle, und sich die MAC-Adresse ändert? Die Käufe verliere ich ja sicher nicht …