I have an xCover FieldPro from Samsung because it is one of two devices they make that are waterproof with a removable battery. It is marketed as a device for first responders and is built with field use in mind. It even comes with a spare battery.

I decided after my S4 Active battery died and I broke the screen trying to replace it that I wouldn't buy a phone without a removable battery. Not easy to find anymore. I did have to sacrifice Qi charging. But the xCover phones have pogo pin charging docks that suited my nightstand charging needs.