I'm working on a site doing some SEO tweaking and I've noticed that Whatsapp takes whatever "og:image" is listed last. For some odd reason, when I list the small image for whatsapp, my twitter card picks that one too, instead of the one I gave specifically for Twitter.
So I'm considering just listing the "og:images" excluding the one for Whatsapp, except when the user agent is WhatsApp's.
With that in mind, I'd like to know what is the user agent given by WhatsApp's crawler?