The most recent update of WhatsApp includes new options to manage privacy and how people see your activity. And now they modified one of its oldest features.
Is that now you can choose whether or not some specific contacts can see your profile picture or last connection time. You must have the latest update WhatsApp for iOS or Android and the steps are very simple.
You must go to Account, then to the Privacy tab and you will find the options of Last Time, Profile Picture, Information and more. There you will find the option of My contacts, except, which will allow you to choose who will not be able to see your activity.