Here is how to update WhatsApp on your Nokia S60 device:
You can also update manually by opening www.whatsapp.com/download/ on your phone's web browser and clicking on Download Now.
Note: You do not need to remove or uninstall WhatsApp in order to update. If you do remove WhatsApp, you may lose your entire WhatsApp chat history. To learn more about chat history read this article.
WhatsApp Support Team