For years, the retail industry has been talking about the rise of mobile and how it may disrupt everything. But according to a new report released today by App Annie -- an app analytics and market intelligence company -- the future is already here. Mobile, especially in the U.S., has already taken over. Looking at both online-first and "bricks-and-clicks" retailers, the study shows that, while mobile is affecting everyone, the U.S. is apparently leading the way. "Most surprising is how well U.S. bricks-and-clicks retailers are doing relative to others outside of the U.S.," Danielle Levitas, SVP of research and marketing communications at App Annie, told me.