Im not sure whether this is common knowledge, but if your iPhone/camera etc is unfortunate enough to get dunked, I've found that soaking it in metho before drying it works very well. The metho displaces the water, and then evaporates off , and the gadget doesn't then rust. If its an iPhone, you need to make sure that it dries off vertically, so you don't get blotches on your screen. It's worked twice for my iPhone - in fact it has actually lasted longer than the rest of he families's phones which didn't get wet.
Andrew A