The world clock functionality is actually built right into the Android 4.2 Clock app. Once it's enabled, you can see the current time for as many places as you want -- and you can even put the info right on your device's lock screen.
Here's all you've gotta do:
1. Open the Clock app.
2. Tap the location icon -- the small symbol in the bottom-center of the screen.
3. Check off whatever cities you want included in your world clock.
4. Tap the Back button.
Voilà -- you're done! The Clock app will now show the current time for all the cities you selected.
If you haven't messed with your Android 4.2 lock screen widgets yet, the world clock will actually be right on your main lock screen panel by default. Just press and hold the clock on your lock screen and swipe your finger downward to reveal the full list of cities.
To add the Clock widget onto a new lock screen panel, simply swipe your finger to the right on your lock screen until the main panel slides over and you see a large gray plus sign. Tap the plus sign, then tap the "Digital Clock" option. To move the widget from one panel to another, press and hold it and then drop it wherever you want.
You can put the world clock on your home screen, too: Just add the Digital Clock widget from your app drawer onto any home screen panel. You'll need to expand the widget to be at least three rows tall in order for the secondary cities to show up.
Not bad, eh?
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