(Now they hitch a ride on the seams of nylon luggage.) Feather beds are much more expensive than down-filled duvets or comforters. They are a heavier construction. So if you live in a damp climate without central heating, it may suit you to use the feather bed as a warm covering. If, on the other hand, you live in a place with all the modern conveniences, it would be better used it to even out a lumpy or hard matress.
Sometimes the liquid contact indicators are placed in such a way that they can be inspected from the outside. For instance there is a LCI in the headphone connector, the dock connector, and near the SIM-card slot of an Apple iPhone.
The next option is to remove moisture from wet iPhone is Silica Gel. You will often find this packaged with new electronics when you first open the box. Silica gel can absorb 15% of its weight in water vapor within a couple of hours. You can buy larger quantities of silica gel for relatively cheap.