Please, assume that at some point your phone will be lost or stolen. I know far too many people that have had their phones just taken right out of their hands. When I ask them if they had Find My iPhone isntalled on their iPhone they looked at me like a deer in headlights.
iPhone and Android both have applications available that will let you find your phone if its lost or stolen as well as let you remotely wipe all the data from it. It works great even if you just can’t locate your phone in your own home or if you weren’t sure if you left it in the car or at work thanks to the GPS view.
They’re totally free apps and Apple offers Find My X for iPhone, iPad and Macbooks with Lion.