I have found out that EWS API is authenticated from OAuth 2.0. I want to call the GetEvents API [1] of EWS. The hard part to understand is how to get the authorization from users for this action. Can someone point me out to the relevant docs on how to register an App and getting the client ID and secret for EWS.
[1] - http://msdn.microsoft.com/en-us/library/aa566199(v=exchg.150)