Usell doesn't purchase used devices itself, but instead fields consumer inquiries, then lists a number of outlets that do, with their current prices, mimicking the kind of comparison shopping long available at, say, travel portals like Expedia.
Although trade-in companies have urged customers to sell their used iPhones as soon as possible -- to get the best price, they've said -- that advice seems misplaced: Prices have generally held steady since early August, and for at least one major buyer, actually increased.
An AT&T 16GB iPhone 4S, for instance, was pegged at $300 by NextWorth today, the same figure it's quoted since Aug. 27. And Gazelle's Thursday quote of $277 for the same phone was up 10% in just two days.
Apple also has a buy-back program -- run by PowerON Service -- that produced an estimate of $285 for a 16GB iPhone 4S, a price unchanged since at least Aug. 29.
eBay's appraisal of $300 for the 16GB iPhone 4S was the same it's generated since at least Aug. 27, but the company said other models had increased in value. Over the last two weeks, said Witkemper, the value of a 64GB iPhone 4S has increased by 5%, while a 32GB iPhone 4 has gone up 7%.
The spot increases may be due to competition among the trade-in companies, which battle for a finite supply of iPhones that consumers are willing to sell.
Some of the firms resell the iPhones they buy on e-marts like eBay and Amazon, while others deal to wholesalers who may ship the older smartphones to emerging markets where dollars are tighter and lower-priced, albeit used, devices are much more attractive.
"It's very competitive," observed Usell's Brauser of the used-device market. "The relatively high-value phones [like the] iPhone 4 and iPhone 4S are in high demand, and will fetch a good retail price."
Apple will reveal the iPhone 5 at the Yerba Buena Center for the Arts in San Francisco, where the company has staged several product launches, including one for the iPad in March. The iPhone event is to kick off at 10 a.m. PT.
iMore.com, the website that in July first claimed Apple would introduce a new iPhone on Sept. 12, said then that the company would begin selling the device Friday, Sept. 21.
Sign up for Computerworld eNewsletters.