I only have charging issues due to heat when in my car. I think the car holder holds in just enough heat to put things over the top. When out of the car, like the other day I watched over an hour of online TV with no loss of charge. In my car, the device can get hot when using data for 15 minutes. I used a small piece of my
cold wrap the other day during an hour long drive and ran Telenav the entire time. Never got hot. 30 degrees C the entire time and by the end of the trip that small piece of cold wrap was no longer cold, but still it seemed not to hold heat like the car holder's black padding. Later the same day, I took a short ride running a podcast for about 15 minutes with no cold wrap behind the device and by the end of that drive the device was already at 47 degrees C. And during the 1 hour drive, I had the device in portrait mode, which usually causes it to heat up faster, but during the 15 minute drive I had it in landscape mode with the slider open. During the 15 minute drive it kept charging, but it always seems to take some trips up to 47 degrees C that don't make me comfortable.