If you have a promo code for a app or iTunes Gift Card but don’t know how to redeem it, you can easily redeem a promo code or iTunes gift card following these simple instructions mentioned.
1. Open the App Store on your device
2. Tap Featured from the bottom of the bar and then scroll down to the bottom of the page.
3. You will then see a Redeem button, tap on this.
5. Enter the promo or iTunes Gift Card code and click Redeem.
6. Sign in if you have not already done so, a Thank You screen will appear when the transaction is done sucessfully.
Follow these same instructions for the iPhone and iPod touch.
(App promo codes expire within four weeks of being requested. iTunes Gift Cards do not expire.)