LEDs make it tough with a point & shoot or cell phone. Iphones only white balance adjustment it to press on a "white" area in the camera view. It would be tougher to do in close ups but in that last pick (for example), if you were to press where the white sand is, you should see an adjustment. Sometimes you have to press a couple of times in the spot to get the camera to recognize what you're doing
.
Note that if you move the camera away from where you adjusted it to, the white balance will reset. It will also rest after each pic.
I have been meaning to try one of these as well. There is a cheaper ebay version...
http://www.olloclip.com/