6261 is your default password. This works similar to most lock screen applications.
You have to enable lock screen in settings in this application and you will see a nice interface of your lock screen. Access is granted when you enter right password or passcode, you will not be able to unlock if you enter wrong password.
Many custom wallpapers to choose from, also real time date and clock is visible which gives a realistic look.
Cool customizations are given in settings page, like sound on or off, vibration on or off.
In case, if you happen to forgot password, just press home screen and your screen will be unlocked.
This application is not for security purposes but it harmless too. Any feedback is welcome and appreciated.