According to sources familiar with Apple’s upcoming iOS 6 mobile software offering, the company’s three major digital stores will see design overhauls. The overhauls are said to be major and they focus on improved interactivity when making purchases in iTunes, the App Store, and the iBookstore. Social is a big piece of the store overhauls, and Facebook integration is being tested in the iTunes Store portion, at least.Apple is still planning to roll out complementary store┬áredesigns for computers later this year.