Anecdotally, I had the first iPhone from day 1, inherited a 3GS and been sporting the 4 since it came out. I've never used a case and the worst damage that's ha

Anecdotally, I had the first iPhone from day 1, inherited a 3GS and been sporting the 4 since it came out. I've never used a case and the worst damage that's happened was a stuck lock-screen button on the 3GS after years of use. I do see lots of people with cases, though I suspect they're for bling and to for the sense of peace-of-mind that they're protecting their shiny object.