Thought I'd share an experience I had yesterday with my cellphone. I always carry it in my right hip pocket, took the phone out to check something and noticed it was warm to the touch, not hot but getting there. After looking closer I noticed the case had separated, front from the back, still together but visibly separating. "So what the h*** is this?" I hadn't dropped it or damaged it anyway. The thing is getting warm enough to now be uncomfortable to handle so I shut it off. Took it in to the store where I bought it and was told that I was lucky to catch it when I did. I had what they call a Thermal Runaway. In my case I caught it early as the battery started to swell it split the front and back of the case and that's when I noticed the problem. Here's what Google has to say about the phenomenon; A swollen lithium-ion battery can be extremely dangerous if left in your device. It could become punctured, causing hazardous gases to escape. A swollen cell phone battery could even catch fire or explode while you're holding it, leading to serious injury. Swollen batteries, while not common, are a significant risk. They are the result of too much current inside a cell of the battery, which causes a build-up of heat and gas. This could damage the lithium-ion battery causing it to overheat and burst into flames. So, I was lucky. It could've happened on the free-way at 70 mph or under 5 layers of clothing while snowmobiling. Isn't technology great?