What happens to old smartphones when they're no longer being used? They just sit around, for the most part.


MarketWatch estimates that all of those old phones sitting around are worth $34 billion. (That's all phones, not just smartphones.) Companies like Gazelle are trying to get people to sell their smartphones to Gazelle, so it can resell the phones around the world and make a nice profit.

Chart of the day shows what happens to old smartphones when they have been replaced with newer models. February 2013Google Consumer Survey (2013)