Trade in my iPhone 6 in exchange for a Nexus 6?

So I got a free iPhone 6. It's still in it's boxed and plastic wrap. I currently own the iPhone 5s but I'm looking into upgrading to something more "advanced". Is it worth selling my unopened iPhone 6 for a new cell phone?

If youre not going to use it you might as well just make sure to sell it lower than its retail price and list its phone provider
or you can give it me. (ill pay for the shipping. )

If you don't want to use it then sell it for the money but the iPhone 6 is the most advanced smart phone on the market.