The basic laws of supply and demand apply here, which means that the increase in iPhone trade-ins has led to lower prices received by those selling their old iPhones. Even prior to the surge in transactions last weekend, prices had already been trending down. Six months ago, the Apple iPhone 5 fetched $337. At the beginning of this month, that price had dropped to $275. Similar declines in price have been seen with both the Apple iPhone 4s and Apple iPhone 4. During the same time period, those trading in the iPhone 4s saw the value of that trade decline from $171 to $115 while the amount received for the iPhone 4 slumped from $188 to $103.
SellCell.com acts like a brokerage firm, looking at over 20 different sites, seeking the best price for a trade.
SellCell.com founder Keir McConomy noted that trade-in prices for the Samsung Galaxy S4 have remained steady, declining to $235 from $250 6 months ago. McConomy said that we could see a sharp decline in the trade value of the Galaxy S4 ahead of the launch of the Samsung Galaxy S5 on April 11th.
source: Sell.Cell Phone via BGR