How to get WhatsApp and other Apps locked

[mark]

Hi friends,
I recently bought Nokia Lumia 520 , and I am wondering that no lock or lock app available in playstore to lock WhatsApp or others App. Can someone tell me that is there is any alteration available to lock Apps?

 

[sanusense]

How can you install apps from PlayStore when you got a Windows OS !
Even though for Windows, AppLocker is one of the best app for Locking files.

 

[shailmartin]

Take these steps to safeguard your privacy over WhatsApp.
Step 1 – Go to Settings and click on Account.
Step 2 – Now click on Privacy.
Step 3 – Over here you can view and change settings for Last Seen, Profile Photo and Status. It is advisable that for all these 3 options, you select My Contacts.