Set up your phone to detect your face or another trusted device before you can unlock the screen. 
	 
 
  
 
	 -  
		  From the 
				Home screen, tap 
				. 
			  
		
-  
		  Tap 
			 , and then select and set up a screen lock. 
		   
		   
			 This will be your backup screen lock method. 
			  
-  
		  On the 
			 Security screen, tap 
			 Smart Lock. 
		   
		
-  
		  Confirm your screen lock. 
		   
		
-  
		  Choose what you want your phone to detect before it unlocks. 
		   
		
-  
		  Follow the onscreen instructions, and then press  to return to the Security screen. to return to the Security screen.
-  
		  Tap 
			 Automatically lock phone, and then specify the idle time before the screen is locked. 
		   
		
To help make Smart Lock more reliable and more secure, you can train 
		
HTC U Play to recognize your face in different situations, such as when you're wearing glasses or sporting a beard. 
		
Tap 
		  Smart Lock, confirm your screen lock, then tap 
		  . Follow the onscreen instructions.