Ever take a phone apart? If not, it's difficult. If yes, you should know how easy it is.
I agree that current phones are pretty chintzy. I have a Startac (10 years old or so) in my hand when I slipped when I was in a wet blacktop parking lot (it was still drizzling). The phone took a ride of about 200 feet down the blacktop. If you look very carefully, you'll notice a spot, about 1/4" diameter, where the kind of pebble grain is smooth. That was the extent of the damage. Do that with most uncased Android phones, even on their backs, and you're probably looking at a new phone. Do it with an old Nextel i58 and you'd need a bulldozer driving over it to damage it. (I had a few driven over by cars. They got dirty. they don't make a phone like that any more.)
12-04-2014 12:47 AM