Various studies have shown that your mobile phone can put you at a greater risk of various diseases as the device acts as dangerous breeding ground for bacteria. But with the S5 you don't need to worry as the phone is dust and water resistant. This means you can wash the phone. The IP67 certification allows users to submerge the smartphone for 30 minutes in water up to 3m in depth. Well, if you try to do it on the iPhone 5S then be prepared to buy a new one.