Apple doesn't provide promo codes for in app purchase products. My content will be in an sqlite database in the app. I'll use a column flag to indicate purchase status. Once the user purchases, I unlock the row by changing the flag.
Would it be easy enough to provide another interface so the user can enter in a code and unlock the item without purchasing? If the user then tries to purchase a product they have used a code for, I query the row for purchase status and display an alert that the user already has this item...or simply indicate this in my app's in-app store.
Does this sound feasible/doable? Possible Apple would reject this technique?