Have you ever dropped your phone down the loo?!

I expect if you have owned a smart phone, that you might have had an incident with it at some stage- perhaps you have dropped it and smashed the screen, but this is much less damaging than contact with water.  Sadly I dropped my brand new iPhone down the loo after only a week of owning it 3 years ago.  Water damage happens quite often, and it invalidates any warranty! 
I advise you to put your phone in a waterproof case to prevent the accident from happening, but
if it happens to you, turn off the phone, take out the battery if you can, and leave it to dry in a sealed bag of rice.  Do not shake the phone to remove water or use a hair drier on it!
A revolutionary new business called "Reviveaphone" offers a special bag for doing this which will also remove corrosive mineral deposits from your phone.  It costs around £15 and has been backed by Dragon's Den.