Every year, Apple makes their "12 Days of Gifts" app available around the Holidays and celebrates Christmas by giving away a different gift each day for 12 days. This can be anything that Apple offers digitally including apps, games, music, TV shows, movie rentals, books, you name it.
The app right now is being featured on the AppStore however, after downloading the app, you will notice the gift giving doesn't start yet and instead you're treated with a countdown. The 12 days of gifts will begin on December 26 and run until January 6. At the time of this article, the countdown is at 17 days!
To download, just follow this link: https://itunes.apple.com/app/12-days-of-gifts/id777716569?mt=8