Here are some simple apps that will help you keep your whatsapp secure and locked from everyone for whatever reason that is.
This app will lock whatsapp and it needs a four digit pin to unlock the app. When one clicks on whatsapp, the app shows them, or you are showed a box to enter a four digit pin to unlock so that you can start whatsapping.
Its Features are:
★ It’s free and has no limitations.
★ Keep your messages safe
★ Capture intruders when wrong PIN entered. Have Fun 🙂
★ Customize autolock time
★ Don’t make you crazy with strange advertising.
★ It is ultra lightweight. Uses low resources and space.
★ Minimun special permissions required
★ Design attractive and simple user interface.
One cool feature about this app is that if your phone has a front camera, each time someones attempts to enter into your whatsapp and they enter a wrong pin, the app captures their face and stores it in the gallery…neat huh!
Whatsdown, be offline on whatsapp
In the same vein, you can also download the whatsdown whatsapp offline app. This app will make you offline on whatsapp. Well, there are times when you don’t want to be disturbed by those incessant whatsapp messages, like right now and suddenly wham. At times you just want to be online browsing the internet in peace than to be disturbed always.
Its cruel to switch off data connection just because of one pest who thinks you are free always. This app will let you shut whatsapp but still use apps like Shazam, Binu, Opera Mini and all in peace.
ZimSmartphones 
Thanks for sharing man, I personally use App Lock which can lock anything on my phone, I can lock an app like WhatsApp, Opera Mini and system stuff like gallery, sms messages and even phone settings, I strongly recomend App Lock its one of the best, if not the best app lock on Play Store, i’ll give a try on WhatsApp Lock, just wanna see how it looks..
Its nice to have sharp readers who leave comments I will try it and write a review, I had not heard of it. Thanks man