Does WAAD Graph API expose Application objects and Service Principle objects?

We have searched for the REST API for accessing application object and service principle object in WAAD at 

http://msdn.microsoft.com/en-us/library/windowsazure/hh974478.aspx

But there is no reference available in the documentation. Using Powershell commandlet we can access Service Principle object but not the Application object. Is there any way or any API available for accessing both?