I also take all my still pictures, and videos of the grandkids with my iPhone. It takes beautiful pictures.
We have a GoPro and use it for underwater videos, but we also have a still camera for underwater pictures and it takes better stills than the GoPro. Not sure if there's something new, but my GoPro doesn't have a viewfinder and no zoom feature either so you don't know what the camera is 'seeing' until you get it to a computer to play back.