I've got a hard waterproof/resistant case on my cellphone.    On days when I have time I take a long walk.   I checked the radar this afternoon and figured I had plenty of time, of course a heavy shower pops up when I'm a couple miles from home.  I got the phone out to call my wife for pickup service and discovered when the screen gets wet it won't swipe.   I'd wipe it off but it was raining hard so it always got wet again.    I did finally manage to get a call off and wife was actually one step ahead and on her way.

Phone works fine again with a dry screen.   Apparently dampness removes the human touch the screen needs.   Just something to keep in mind.   My luck I'll be in an actual emergency and the screen will be too wet to work.   And yes I was soaked by the time wife arrived but glad to see more rain.