Introducing a Waterproof Case for iPhones by Sanwa. Sanwa is a company in Japan that introduced this Waterproof Case for iPhones. This case features a sealing mechanism design to keep prevent the water from entering. It allows you to use your phone in water and even listen to your favorite song. You can even use the camera while in water. It has a lanyard so that you can wear it around your neck. iPhone users need not worry in using their iPhones in water.