iPhone 4 resales were up nearly 883 percent in the month leading up to the iPhone 5's introduction. While buyers take all models, iPhones are what people trade in most. - Apple is expected to sell quite a few iPhone 5 handsets this year. Investment firm Jefferies has calculated that 170 million global smartphone subscribers will come out of their contracts in the second half of 2012, and 450 million more will do so in 2013. Contracts aside, Topeka Capital analyst Bri...