How can i tell which apps have access to my google account topic

Ok,
so this is more a general question about google rather than ANDROID, but android is google haha, ;)

anyway, you know for example when you give an app permission to access google or sync with gmail it says

"the following application will do these things;

see your contacts" etc

etc

etc

so how do i check what apps have been given permission?
also theirs some app called BOXBE and i had to click onit to send seomeone a email and i think i let it access my emails LOL so please tell me what to do