You should invest in a bumbag, like this.
I found a lump in a bucket as i was mixing. I thought balls, he a pain anyway so smashed it about a bit as i mixed. Tipped it onto spot and eventually he found the lump. Turned out to be my fone that had fell into three bucket from my pocket. I lobbed out into a water butt and left it a few hours them pulled it out and it worked perfectly.
It was a land rover fone by sonim.
Pretty crap off you want to do more than ring someone but pretty Indestructable.
I've got an iPhone 4S and use an Otterbox Deffender case, I get a little bit of dust under the screen protector but its pretty safe when in its cases up. I had a 3GS before that in a Deffender and that one was better sealed than this one.
The best cases to go for afaik are the Lifecase ones from the US, the are watertight and you can use your phone underwater! Bit expensive though...
Used to carry my old Nokia in a plastic bag inside a case but condensation ruined it.
Also have our phones insured, we could drop them in a bucket of water then run over them and they'd be replaced straight away.
just got the s3...... pukka phone it even made me a bacon sandwich today wen i woke up, fella in carphone wareshouse said it pisses all over the i5 and apparently there was some review of the 2 phones and out of ten catagories the i5 only won 2