By default, WhatsApp will automatically set your Privacy Settings to allow any WhatsApp user to view your read receipts, last seen, profile photo and status. If you don't share your last seen, you won't be able to see other people's last seen. Please note there is no way to hide your online status.
To change these settings, simply open WhatsApp > Settings > Account > Privacy Settings.
You can set the following options separately for last seen, profile photo and/or status.
Your last seen, profile photo and/or status will be available to all WhatsApp users.
Your last seen, profile photo and/or status will be available to your contacts from your address book only.
Your last seen, profile photo and/or status will not be available to anyone.
If you uncheck Read receipts, you will not send read receipts. You will also not be able to see other users' read receipts.
Learn how to configure Privacy Settings on: Android | iPhone | Windows Phone | Nokia S40 | Nokia S60 | BlackBerry 10
Cheers,
WhatsApp Support Team