Is there a way to set up my iphone so that I only receive vibrating notifications? What I want to do is have the phone ring on incoming calls when the ringer switch is set to "on" but I want only vibrating notifications for sms, emails, etc. Similarly, when I have my ringer switch set to "off" I want the phone to only vibrate for incoming calls, sms, texts, etc. Is this possible on the iphone?