I bought this one a couple months ago and have used it skiing and in the ocean and it works great for both.
https://www.amazon.ca/gp/product/B01...?ie=UTF8&psc=1
It's half the price of many go-pros because is doesn't do 4k, but looks great on 1080/60fps. Sound is very good. This is a much better camera than the knock-off go-pro I originally bought (you definitely get what you pay for - the knock-off broke quickly). The still camera on this is only 8MP, but seems to take decent pics. I also like that it is inherently waterproof (no waterproof case required). Battery also seems very good.
If you are in the field and want multiple charges, consider buying something like this:
https://www.amazon.ca/JETech-2-Outpu...rtable+charger
This model would recharge a go-pro 4 or 5 times easily.