We use Samsung Galaxy V units for all our delivery drivers and up until now we haven't had any problems. I think something must have changed though because as of last week all our phones have started periodically restarting. I'm not sure what was installed before but they're all now on KitKat 4.4.2. I've tried a factory reset on all the devices and checked all sorts of settings to no avail. Does anyone have any suggestions on how we can fix this? It's causing havoc with our business. It must be a software issue to be affecting all our phones at the same time. Thanks in advance!