Unlock free In App Purchase with Code

I know that it is not allowed to unlock content with an own code system. You must always use In-App Purchases.

But is it allowed to build a code system where access to a free In-App Purchase is unlocked?

Thanks in advance.

You must always use In-App Purchases.

Correct. An IAP is an IAP, regardless of tier.

Access to any product in that context is only allowed via Apple's IAP'ing process.

Ref. 3.1.1 in the ASRGs.
Unlock free In App Purchase with Code
 
 
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