Protect and hide your recent activity
If you have installed the latest version of WhatsApp, one of the things that might be puzzling you is the change on the activity labels. Used to text people only if they had recently used the app or just looking for friends available for a chat during a lunch break, timestamps are something useful. If you allow me to say, this is one of the great features of the app over alternatives like traditional SMS.
Now, like in any social networking there is always a concern about privacy. WhatsApp provides the option to disable the activity label on your profile to avoid situations like being spotted online when you weren't supposed to be using your phone. Can you imagine your teacher finding your "last seen" while you were taking an exam or your boss when you were meant to be working?
Activity labels can be deactivated directly within the iOS app tapping on Settings → Chat Settings → Advanced (scrolling to the bottom of the page). The Advance settings has a switch to turn Last Seen Timestamps on and off to change how your recent activity is displayed publicly. There is a small disclaimer noting the changes can take up to 24 hours to take effect and a limitation of one toggle per day, which I found curious.
WhatsApp doesn't have privacy settings per contact or per group, so you will disable this feature for all your contacts. The only way around it to hide your activity from a particular person but not to the rest of your contacts is to block, which also brings with it other restrictions — like not receiving messages from this person.
I still like a lot to see people activity as it makes the app more of a mobile instant messaging service with a lot of quick interactions. On the new iOS 7 interface this label is right under the contact's name when you are on a chat view, more often than not showing a 'tap here for contact info' that fades away quickly.