How to redeem a promo code or gift card with iTunes on Mac or Windows

[iMore.com]

iTunes, iBooks, and App Store gift cards as well as app promo codes are all redeemed the same way. One of those ways is through iTunes on your Windows PC or Mac. If you've received a gift card or a promo code, you can fire up iTunes and redeem your card for store credit in just a matter of seconds.

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