While deer hunting, or experiencing the great outdoors, I usually carry my cell phone in case of emergencies or I want to check the time.
If you have ever had to take a cell phone in for repair, the repairman usually checks a small strip of paper inside the phone to see if moisture of any kind, has gotten inside the phone. This will usually void any repair warranties.
If I'm involved in any type of vigorous exertion that involves the upper body;I keep my phone in a chest shirt pocket, for easy access, I take a small plastic bag, usually a newspaper bag, and place my cell phone inside. This keeps any moisture or condensation out of the cell phone. I cut the bag just enough, so I don't have to keep placing my arm the length of the newspaper bag every time I want to check it.
The small strip inside of my phone is moisture free!