Over the next 7 to 10 years, major tech, retail, and financial players will duke it out to make the "mobile wallet" a reality, allowing people to pay for everything with their smartphones. Whoever gets there best--not necessarily first, and almost certainly with partnerships--could theoretically control the multitrillion-dollar U.S. payments industry. Here's the likeliest battle trajectory, based on interviews with leading industry analysts.
A version of this article appears in the December 2011/January 2012 issue of Fast Company.