Buy and sell used android mobile phones
While eBay might seem the best first option to buy or sell an used android phone (or tablet), there are other specialized venues which might suit this purpose in a better way.
They have had press coverage already. You may want to check them out when hunting to buy or sell an used android phone.
A good one for refurbished phones is ReplaceYourCell.com
If you want to support a charity with your used phone, ExchangeMyPhone.com has that.
As mobile devices generations continue to evolve, used phones are more and more powerful. To the point of easily fulfilling the needs of plenty of people. The used phones market is out of any doubt getting better.