Get ready to streamline your Starbucks latte experience: The coffee giant says that it will launch its so-called Mobile Order program in Portland this year, and that it will make across the mobile order and payment program available in the rest of the U.S. by 2015. For Starbucks, it's all about tapping into its huge, Millennial customer base, who widely prefer to use their smartphones to make purchases as well, and it estimates that 15% of Starbucks purchases are made with mobile devices.