The Samsung Galaxy S3 (and Note 2) has a neat feature when docked to a Samsung multimedia dock; it can automatically display the desk home screen. The desk home screen is a useful display with a clock, calendar, local weather and multimedia shortcuts. It's a nice companion display when you're charging your S3 at your desk. However, you don't necessarily need a dock to use the desk home screen.
If you're using a third-party smartphone stand with a separate charger, you can still make use of the desk home screen.
To use the desk home screen, go to the built-in clock app on your Galaxy S3 or, then swipe the tab list to the left and choose the Desk clock tab. Tap on the full-screen icon to enlarge the screen and display the shortcuts.
Keep in mind that after a minute or so, the screensaver will come on with the time, date, and weather (if enabled). To view the desk home screen again, just tap the Back button.