The 2 versions both have accelerometers built in that, in theory, detect the phone being dropped even before it hits the floor. This allows the phone time to "park" the disk heads before they hit the platter! However, depending on the severity of the "knock" damage may still occur. These tiny hard disks are not as well proven as most pc hardisks so we may well see that failures are not always associated with drop damage anyway. ALL phones are quite sensitve and will not tolerate repeated dropping as there are quite afew delicat components on board. You should see the state of a lot of the phones I see in for repair, I really don't kow how people can treat them like they do!