I'm kinda worried. Read various articles saying with heavy web browsing and gaming this device can heat up? Just wondered do people think this is a real issue to be worried about, if you've experienced this?
My worry would be battery integrity. I'm used to BlackBerry and removable batteries. So I never worried too much because I could just replace it if it failed (which mine have on more than one occasion). Now that I have a Z3C, I try to keep the temp from going too high or low.
Sometimes my phone will randomly heat up and drain my battery, but I just kill all the apps that are running and reset my phone to solve it. Other times when I'm playing a game like X-Com it will get pretty warm, but I haven't run into any issues with the phone getting that hot.
No it's not a big issue. The only times you will have overheating is when you use intensive apps, such as playing heavy games, 4k video take and those others stuff.
The only times my z3c has heated up is when upgrading to Lollipop, playing Dead Trigger 2 and using Google Maps for a solid half an hour (GPS, Wi-Fi is turned on and screen brightness adjusted to auto).