Timestamp Last seen gives us an idea about when the person you want to chat was online. It's a great feature, but the function becomes really annoying because it reveals whether you are online , and no. You can not hide from your friends and they'll keep talking to you.
So if you want to hide this " last seen in the" time stamp account then download WhatsApp application will not last seen. After installation , select the option to hide their " Last seen in the ' time stamp . NO ROOT REQUIRED .