Apple has at last made promo codes for in-app purchases available to developers. For the longest time, promo codes were only available for app downloads, but now individual in-app purchases can have promo codes generated for them. This means that developers of free-to-play games could run contests for in-game currency. Or for freemium unlocks for press or customers, those can be handed out as well. Apple enabled this feature only recently to developers, but it’s already working for developers – I was able to test it out with the upcoming ZenDots 2 and its level unlocks.
This is definitely an “at last!" feature for Apple, because not only has Google Play promo codes supported in-app purchases (though for whatever reason Google doesn’t support pre-release promo codes), but because the App Store has had this functionality for a while! There was a situation with a Real Racing 3 promotion that used a promo code specifically for in-app purchases, but it didn’t become available to developers at large until now. Better late than never.