

Developers have long been able to offer promo codes to download a paid app, but until today, there was no simple way to offer access to in-app purchases.
Developers are able to give away up to 100 promo codes for each in-app purchase item, up to a maximum of 1,000 codes per app every six months.
Article Link: Developers Now Able to Offer Promo Codes for In-App Purchases