After posting about Apple's PowerON partnership for trade-ins, I was contacted by several parties who hoped I could give their services a mention (all prices are USD).
Sarah Hahn of Allison PR represents Glyde, a service she says pays out up to $460 for a 64GB 4S versus the max $345 available through PowerON. That's a huge difference, and we recommend caution when dealing with any vendor whose prices seem too good to be true.
Ashley Halberstadt of Blast Media points to NextWorth, which offers both cash and gift-card trade-in options. Their price lock guarantee will extend through October 1st. Their 64GB 4S trade-in is going for $351.
TUAW readers also chimed in with thoughts and advice. Reader mindflayer writes that he sold his to GameStop. "Cash in hand, more money offered than Gazelle."
Chris Braden went with eBay instead. "I had a great experience with eBay instant sale when the new iPad came out," he wrote. "They ran a promotion where I got a lot more money than anywhere else, and I did the whole transaction with my phone."
Smythe Richbourg used NextWorth. "It worked like a charm, and I got a decent price. Looking at what they're paying now, however, the prices are not too good. eBay is much better, since you get what the market will bear. I've sold both my original iPad 16 GB ($200 - sold in less than 2 minutes!) and an iPhone 4 32 GB ($400 - sold in a few days) there in the past few months, for about twice what the buy-back sites were offering."
James Winder had some advice for UK readers. "I live in the UK and for the last couple of years I've mostly used a company called CEX (Computer Exchange) to sell old iPhones to. You can get a price for your particular phone straight away online and then go into the store and receive cash for it. I usually buy a new iPhone first, set it up and then when I'm happy with it I wipe and cash in the old one."
He mentions that, at least in the UK, independent pawn shops give much better prices for iPhones than the larger companies and carriers. He adds, "Oh and a lot of friends always pop up on Facebook offering phones for sale around the time a new one comes out and usually don't have trouble selling them to other friends."
Got some trade-in/reselling advice? Drop a note in the comments.