Communicate between php session to ember-application

I build a website based on cms(wordpress) and on his website it has some sort of form, when you successfully fill out the inquiry it will going to redirect to subdomain which is the ember app

my question is how can i exactly communicate the php session to ember-app? if your going to ask me why i build a seperate app for that is because there's a lot of functionality i want to add eg(sms verification,dashboard and so on) which is not possible to wordpress