title: Change Badge icon when notified
body: <p>I'm using Xamarin Forms and I manage to send notifications to my applications in both iOS and Android using Firebase. I want to change the Badge icon every time a notification arrives, with the application in the background. 
  Similar to Twitter or Whatsapp. </p>
  
  <p>How can I change the Badge of my application when my application is in the background?</p>