An anonymous reader writes "Today Apple announced the launch of a trade-in program for iPhones. Users will be able to send in their older devices and get credit toward new ones. The announcement precedes an event on Sept. 10th at which Apple is expected to announce a new iPhone model. The trade-in program is being managed by a company named Brightstar, with whom trade-in value maxes out at $336 for a 16GB iPhone 5. The 16GB iPhone 4S, 4, and 3GS max out at $221, $151, and $52, respectively. (The value drops depending on the device's condition, of course.) 'With its new program, Apple steps into a crowded field of competing programs offered by companies such as Gazelle, Best Buy, GameStop, Amazon and others, all of whom accept older iPhones for money. The broader market for used smartphones has been estimated to bring in as much as $5 billion in sales by 2015. With Apple participating as well, more smartphone users may opt for the trade-in option, and could potentially send that estimate even higher. Running its own program would give Apple a way to drive more iPhone sales within its own stores rather than seeing sales from carrier partners, and drive more traffic through its retail stores as well.'"