Here's an idea for the phone. You can hang it from your neck and keep it close to your body in your jacket to save the battery power. You can still use the phone as the clear plastic doesn't prevent touch sensitivity. It is waterproof so If for some reason it falls through the hole it will float so you can recover the phone, also saves the phone from water splashes.
I also cut a piece from a bubble envelop to size and insert it behind the phone to add more buoyancy (as seen on the left of the photo). Works great, I no longer fear losing my phone while fishing.
