I would like to be able to shutdown and also lock the iphone (3G) just by tapping an icon on the screen. I have SBSettings, but that requires several key strokes to accomplish this. What I'm looking for is an app that will place an icon on the screen so all you have to do is tap the icon and it will lock or shutdown the phone. I can across ireboot, but it didn't work (maybe only works on ios 3.*).