In reply to madtoclimb:
I've got a life proof case for my iPhone 4. I got the phone free with my contract so I didn't mind spending the 60quid or whatever it is for the case. The case isn't as tough as some but neither is it particularly bulky so it's comfy to just leave on the phone all the time. I drop my phone regularly and will just have it in a pocket when running so it's been soaked through a few times. No issues whatsoever.
I know you asked for phone recommendations but that could be an option? Given they do them for a range of smart phones...