Rather than go along with Apple's requirement of a 30 percent cut of sales, Audible.com has removed the "Shop" button from within its app that linked to the company's website. Customers will now have to go through a series of steps to create a "Shop Audible" home screen link that will serve the same function on their mobile device. The change comes as Apple is beginning to enforce its rules requiring 30 percent of sales made through in-app purchase links.