I just went snowboarding yesterday and experienced this. I have a galaxy Note 4. The conditions at the snow summit, a mountain in southern california were terrible. It shouldnt have been a bad experience however it felt very cold but unable to produce snow because it wasn't freezing enough. so it was raining but really damp because the water molecules couldnt freeze up enough to stay out of my ski clothes or to stop penetrating my bones which is a very very chilling feeling. i dont know if this dampness is what affected my phone or the cold itself but no one should go skiing in the rain. anyway i put my phone in a ziploc bag but only while i was on the ski lift so a little moisture got in there. it was working ok in the ziploc bag for a while but then it kept restarting itself. i didnt want to fumble with it up in the air, while it was raining, gloves, etc so i didnt bother pulling out the battery. after the 3rd time, it stayed off but it had at least 50% charge. mind you this battery has also been abused and doesnt hold a charge the best it could, not like it used to. when i got back to the lodge, it was fine. i kept it on and went back out there without the ziploc but never took it out of my pocket again. and at the end of the day, it was fine and still turned on by the time i was leaving. i think taking it out of the pocket and using it for a couple calls is what pushed it, i couldve kept it on while running my ski tracker app but i didnt want to mes with my phone anymore. even though i had a case and ziploc bag protecting it (surpringsly it works well with a ziploc quart bag!) too blurry for pictures though because its a freezer bag and its thicker. a sandwich bag is thinner and might be clearler but i could talk on the phone clearly and just set it up in a dry place