Looks like soon you'll be able to use Siri to read and send WhatsApp messages as well as make WhatsApp calls on iOS devices. A leak - which reveals an explanation text that's shown to users when prompted to give WhatsApp access to Siri - suggests this. It's worth mentioning that Siri can only be used with Apple's own apps (and a select number of third-party services) at the moment, but that'll change with the release of iOS 10, which will allow the integration of the virtual assistant with third-party apps. So while there's no official confirmation on WhatsApp getting Siri support...
Source: http://www.gsmarena.com/siri_support_coming_to_whatsapp-news-20065.php
