Facebook also used xmpp in the past, it appears: https://eion.robbmob.com/blog/2009/11/04/xmpp-facebook-chat/ https://eion.robbmob.com/blog/2009/11/04/xmpp-fac

Facebook also used xmpp in the past, it appears: https://eion.robbmob.com/blog/2009/11/04/xmpp-facebook-chat/ https://eion.robbmob.com/blog/2009/11/04/xmpp-facebook-chat/ Supposedly WhatsApp is also based on xmpp: https://en.wikipedia.org/wiki/WhatsApp https://en.wikipedia.org/wiki/WhatsApp It is a great pity that something that has created so much value for so many companies now somewhat languishes. A real shame. Not that xmpp isn't great, but it'd be so much better if the platforms that benefited from it had only contributed back more.