How do I use emoticons and smileys?
At this time, we do not have emoticons built into WhatsApp for iPhone. However, emoticon support is built into the iPhone by using the Emoji keyboard. Go to iPhone Settings > General > Keyboard > Keyboards > Add New Keyboard then select Emoji.
Once the Emoji keyboard is enabled you can access it here:
Please note that iOS 6 has introduced additional emoji characters. In order to send and receive all of the new emoji characters, you will need to have upgraded your iPhone’s software to iOS 6 or later.
WhatsApp Support Team