Not coincidentally, Apple is expected to launch two new iPhone models next month, on or around Sept. 20, 10 days after a scheduled media event. Although the company has not disclosed specific timing or the names of its forthcoming devices, reports suggest they will be called iPhone 5S and the more affordably priced iPhone 5C.
The iPhone 5S should come with a more powerful processor -- possibly a 64-bit ARM-based A7 chip -- and a longer-lasting battery and a sharper camera. The iPhone 5C is likely to be similar to the current iPhone 5 in hardware and performance.
Much of the pre-release coverage of imminent iPhones has focused on color options: The iPhone 5S is said to come in black, white and gold. That might matter more if protective iPhone cases weren't needed.
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However, the iPhone's software is likely to get more attention than its hardware or color scheme. Apple's iOS 7 mobile operating system features an extensive interface revision and such changes tend to generate passionate responses, pro and con.
Todd Day, an analyst with Frost & Sullivan, sees Apple's iPhone recycling program as an effective marketing tool.
"The trade-in program for Apple will attract customers to other Apple products and accessories," said Day in an email. "Similar to the effects of a retailer like Best Buy offering store credit, Apple can provide their customers with credit toward Apple products and services."
Apple characterizes its program as "helping support the environment." That might be the next best thing to not taking metal, minerals and other materials from the ground to manufacture new iPhones in the first place.
Apple will not be alone in trying to tempt past iPhone buyers to buy again. Best Buy is offering 50% off the purchase of an iPhone 5 with a two-year contract to those who trade in a working iPhone 4S or iPhone 4. Amazon and Radio Shack also have trade-in programs, as do AT&T, T-Mobile and Verizon. And there are online companies that offer cash for unwanted electronics, such as Gazelle.com.
According to the Los Angeles Times, Apple Stores will be evaluating used iPhones and offering somewhere between $120 and $250 in credit toward a new iPhone, including a two-year contract.
Gazelle.com currently is offering $205 for an iPhone 4S in "good" condition, with AT&T or unlocked, and $215 for one in flawless condition, without any requirement to enter into a contract.