BARCELONA — Japanese women are so fond of their phones, they even use them in the shower, say manufacturers. This makes waterproofing a must - also good against rainstorms and accidents while texting on the toilet.

Panasonic and Fujitsu are touting their waterproof and dust-proof phones as they seek to charm the overseas market at the world's biggest mobile phone show in Barcelona this week.

A man places a Panasonic waterproof smartphone on a glass of water during a presentation at the Mobile World Congress.

"In Japan, you can't sell a phone if it's not waterproof. About 90 to 95 per cent of all phones sold now are already waterproof," Panasonic executive Taro Itakura said in an interview at the Mobile World Congress.

"Why? This is very unique - young Japanese women prefer to use their [mobile phones] even when taking their showers," Itakura said.