title: Toast notification on windows phone 8 without sound and vibration
body: <p>I'm going to make a simple toast notification using periodic task of background agent, what 
  I'm asking is how can I show notification in specific time, but without playing sound notification or vibration, is there any way to achieve it?</p>
  
  <p>Since what I've seen at <a href="http://msdn.microsoft.com/en-us/library/hh202962%28v=vs.92%29.aspx" rel="nofollow">http://msdn.microsoft.com/en-us/library/hh202962%28v=vs.92%29.aspx</a> that VibrateController is unsupported api in background agent</p>
  
  <p>Thanks!</p>