There is waterproof specification levels. I haven't met one consumer product which doesn't let moisture in. I live in a hot country (not over 40ºC mind you)
If I not being precise, keeping your phone in your jeans deep tight pocket when you are sweating or raining will cause you problems. It might seem too many coincidences for you, but it is common enough that some of us avoid keeping the phone in the pocket.
In a cold climate it’s the opposite problem. You need to keep the phone warm when you’re outside, otherwise it becomes extremely cold, and then becomes a condensation magnet when you come back inside!
If I not being precise, keeping your phone in your jeans deep tight pocket when you are sweating or raining will cause you problems. It might seem too many coincidences for you, but it is common enough that some of us avoid keeping the phone in the pocket.