Are you worried about exposing your PIN while you unlock your phoneHere comes Knock Lock - Applock for the rescue. The innovative Lock Screen that will leave intruders baffled.To enable Double tap to lock, please activate Knock Lock as "device administrator". It's only used for lock device on double tap on floating icon.
The most secure lock screen and Applock on Google Play. With App Lock, nobody can check your photos, videos, messages and apps. The patented PIN pad is the ultimate in privacy and will keep anyone from seeing your PIN, even if they watch you input it .Go ahead use this Screen Lock & Applock to challenge your friends to see if they can crack your code.

Features
- Prevent Unauthorized Access
- Invisible path to Unlock Pattern/lock change every minute.
- Helps preventing accidental calling.
- Prevents others from using your device.
- Superbly rich graphics.
- Consume less memory and battery, Simple and Clean device.
- 100% safe and secure
- 12 hour and 24 hour format both supported
- Unlock vibration enable/disable
- Unlock sound enable/disable
- Highly secure lock screens
- Choice to set knock position on screen.
Using Method
Smart Phone Lock will set the current phone time as your
unlock PIN for the lock screen. It will change the PIN magically on
every minute! So, each time you unlock the device, the PIN will vary and
you need not worry about prying eyes around you. The best part is, you
need not memorise anything to remember the PIN. The modifiers will allow
you to enhance the security to the next level. Important
You can also hide Smart Phone Lock app icon from the App list by selecting hide icon option under settings. If you hide the icon, it will be tough to find you are using Smart Phone Lock. You can launch the app by dialling/calling 1234 in the phone. If you forget the PIN , Don't worry.At any point of time, you can use your default PIN which you have entered during the app installation. Default PIN will act as backup code to unlock your phone. So, you can log in with default PIN. Even if you forget the default PIN, after entering 3 wrong default PIN , there is an option to get the default PIN through SMS to the registered phone number.