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Set a world clock as a widget on the lock screen and it will open the clock app when you tap on it.
 
Set a world clock as a widget on the lock screen and it will open the clock app when you tap on it.
I imagine being able to touch on the clock anytime in the OS(say while surfing the web, or in any other app that’s showing the time in the corner of the UI) and open the built-in clock app.
 
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