At Apple's (AAPL 0.76%) recent Worldwide Developers Conference, CEO Tim Cook announced that iTunes has a whopping 575 million active accounts with credit and debit cards on file. This revelation, coupled with a new iOS 7 feature known as AirDrop, could indicate that Apple is getting closer to entering the mobile payments space. In the video below, Fool contributor Steve Heller explains why eBay's (EBAY 1.03%) PayPal unit could have the most to lose.