This is a sponsored post written by the sponsor, Glyde. Please click here for more information on sponsored posts on 40Tech.

For those of us out there trying to decide if our current iPhones are good enough in the shadow of the iPhone 4S, the cost of upgrading is usually a big factor. One way to take the sting out of this transaction is to trade-in or sell your old phone. The decision to trade-in or sell is similar to when you are getting a new car. Trading-in is easy, but you get a rock bottom price. Selling in an existing marketplace like eBay or Craigslist will get you more money, but is a hassle. Bridging this gap for potential sellers is Glyde, an online marketplace with an incredibly simple interface which takes the hassle out of selling, and offers the highest price possible.

Glyde was conceived, designed, and built to make it remarkably easy for anyone to sell their stuff. Listing products for sale only takes a few minutes. When your item sells, Glyde sends you a pre-stamped, pre-addressed mailer. All you have to do is drop your item in and give it back to your mail carrier. When it arrives at the buyer, Glyde deposits payment promptly into your account. Right now, Glyde lets you sell video games, DVDs, iPads, Kindles, and other consumer electronics. In anticipation of the release of a new iPhone model, Glyde is now allowing users to sell their pre-owned iPhones.

Unlike a used car, an iPhone does not depreciate as soon as you take it out of its case. In fact, trade-in sites are offering their best deals ever, but even these pale in comparison to the prices that phones are selling for on Glyde. The iPhones 3GS and 4 are selling for around $200 and $400 respectively, almost twice the amount offered by trade-in sites. There are no upfront costs or listing fees so it’s risk free to try. Sell now.