Unless kept unlocked automatically, your phone locks the screen five seconds after the screen turns off.

To increase or decrease the amount of time before automatically locking the screen:

1. Go to Settings > Security and privacy.
2. Tap Device lock.
3. Next to Screen lock, tap .
4. Tap Lock after screen timeout, then select a duration.

You can manually lock your phone by pressing the Power button. If you want the Power button to turn off the screen but not lock it:

1. Go to Settings > Security and privacy.
2. Tap Device lock.
3. Next to Screen lock, tap .
4. Tap Power button locks instantly off .

After the screen turns off, your phone will still lock after the time set for the automatic lock.

You can hide your PIN or pattern to prevent others from viewing it when you unlock your screen.

To hide patterns (if you're using a pattern screen lock):

1. Go to Settings > Security and privacy.
2. Tap Device unlock.
3. Next to Screen lock, tap .
4. Turn Make pattern visible off .

To control whether characters briefly display when you enter a password to unlock your phone or log in to websites and apps:

1. Go to Settings > Security and privacy > Privacy > Privacy controls.
2. Turn Show passwords off .