i. Open the App Store application on your iPhone, iPad, or iPod touch.
ii. Tap “Today” at the bottom of the screen.
iii. Click on your photo or the sign-in button at the top of the screen. You can also tap the “Redeem Gift Card or Code” option if you do not see the option.
iv. Use the camera by tapping “Use Camera” and following the instructions to use it. You can also enter your redemption code manually if you run into trouble redeeming your iTunes gift card. To do so, tap “You can also enter your redemption code manually,” then follow the instructions. Be sure to enter the 16-digit code beginning with X.
v. Click ‘Done’.