How do you purchase in-app game extras like gems for the game Clash of Clans with an i-tunes gift card? I have downloaded three $10 gift cards on my i-phone 4 and can't seem to purchase any extra game stuff (gems) without it charging my credit card that I have attached to my i-phone. So what I am saying is I have $30 worth of i-tunes gift cards downloaded on my i-phone and can't seem to use it, not for what I want anyways...
Thanks any help would be great!
