The 20% savings on Apple iTunes gift codes (US App Store) are back courtesy of Bestbuy.com’s Deal of the Day promo. For those not familiar, they’re iTunes gift cards in digital form. Once purchased, a redeem code will be sent your way shortly after via email, though the catch now after the recent changes is that you must own a US credit card or Paypal account to make the purchase. The codes can be used to buy music, movies, TV shows, audiobooks and of course, apps on iTunes and the App Store. The gift codes start at $15 (now $12) and go all the way up to $100 (now $80). The deal ends at midnight EST tonight, so head on over to the landing page here to take advantage of the savings.