You will get email or mail. Either ones you will get. If you provide email address in the application you will get approval in the email. That's how I got it. Try to keep checking your junk folder too. Hope this is help.
My wife in Brazil received a phone call. It took nearly a month as CIC only called once a week and my wife
happened to miss the calls the first three weeks. The fourth week her cell phone never left her hands and
she got the call with the happy news.
Then it took another month to receive her passport and visa but this was delayed from a postal strike.