i have to program a web app that collect all emails from different accounts and display it..
like when you register into web app you add your gmail account& yahoo account& hotmail account and the website will access to your accounts and bring all your emails and calendar and display it.. i should do that using java EE (servlet) & nodejs & angular but i don't know how could i to access for the emails .. is there any protocols i can use or API i can use to do that ?