Kyocera demoed its Torque G02 and Digno Rafre devices here at Mobile World Congress in Barcelona (though they were announced a few months before the show). The former is saltwater resistant, while the latter can be washed with soap.
The 5-inch Digno Rafre can be washed with soap, unlike most waterproof phones. That comes in handy when you happen to spill food or get some grease on your device.
The Digno Rafre is only sold in Japan so far. The majority of phones sold there are waterproof.
Soap has detergents, which can dry out the rubber seals and gaskets inside regular waterproof devices and make them brittle.
The Digno Rafre, however, has gaskets and seals made of different, more durable materials, that are protected against these corrosive and drying elements.
The device can also be washed in water as warm as 109 degrees Fahrenheit (43 degrees Celsius).
Because salt is corrosive, most waterproof handsets are only protected against freshwater. The Torque G02, however, can withstand a dip in saltwater, so don't be afraid to take it swimming in the ocean.
Though these phones are still pretty niche, it's still to see Kyocera taking the steps needed to bring us towards the ultimate dream: being able to use our phones anywhere, anytime, without having to worry about them breaking.