Mobile Security
Add Android Screen Lock
Go to your applications page
Find Settings
Under Settings choose 'Lock Screen'
Select 'Screen Lock'
Select 'Pin' (or pattern if you rather)
Set your new pin, confirm you new pin by entering it again
To change the screen timeout length, go to 'Settings', 'Display', 'Screen Timeout'.
Add iPhone Screen Lock
Go to "Settings"
Go to "Touch ID and Passcode"
Scroll down and tap "Turn Passcode On"
Type in passcode
Verify passcode
To change the screen timeout length, go to "Settings," "General," "Auto-lock"