Sometimes, you just don't want to hit the Power button to turn your screen off. In the current age of touchscreens, you've got to wonder why we even have physical keys anymore.
There are actually plenty alternatives to using the Power button on your Samsung Galaxy S3. You could let gravity do the work for you, or you can create an invisible "screen off" shortcut, which can be hidden anywhere on your home screen.
While both of those options are find and dandy, who wouldn't want one more? If you want to turn off your phone without hitting a button, or simply like having other options, then... more