Just saw this on ibooks store.
Apple has just released this year's 12 Days of Gifts app for iPhone and iPad. Download this free app, and every day at midnight local time, between December 26 and January 6, you'll get offered a free gift from iTunes. Gifts can include apps, iBooks, music, movies and movie rentals, and TV show episodes. The exact content and availability will likely vary by region, but hey - presents and presents, right?
http://www.imore.com/apple-releases-...r-26-january-6