How to Hide Last Seen Status on Whatsapp

This is an app of android which disables the network packet data when you wish to hide
your last seen status. But the drawback of app is that you can not hide your status while
you wish to chat with someone for long time.

Because this app basically disconnects your handset from packet data when you enter
whatsapp, so servers of whatsapp dont get your status that you are using it and then after
reading the messages when you close the whatsapp , it again enables the internet active
automatically so in this way you get to read the messages from your contacts without being
noticed by whatsapp servers and hence your last seen status is not updated.