I think the more typical behaviour is to buy on contract and thus upgrade on the one year or two year interval that coincides with the contract. A quick Google

I think the more typical behaviour is to buy on contract and thus upgrade on the one year or two year interval that coincides with the contract. A quick Google suggests that even two years might be a bit long for Americans: http://www.phonearena.com/news/Americans-replace-their-cell-phones-every-2-years-Finns--every-six-a-study-claims_id20255 http://www.phonearena.com/news/Americans-replace-their-cell-...