Apple is set to roll out its iPhone trade-in program, where customers can swap their old handsets for credit toward newer ones. Beginning this Friday, Apple Stores in New York City will accept trade-ins of dated iPhones. This program, which iPhone owners have been waiting for impatiently, is being executed to increase sales for the new iPhone due out next month. While other companies have similar trade-in programs, old iPhones have greater value than their counterparts. Staff members at the Soho and Upper West Side stores said trade-ins would start Friday, confirming the program exists. Plans for the Grand Central Terminal, Fifth Avenue and Meatpacking District branches were unclear. New iPhones are expected to hit on Sept. 10.