title: Sending messages(notification) to a group - Android
body: <p>I am writing an android application in which i need to send a notification to a group of users. </p>
  
  <p>I have two group of users in the database. If a user press a button "Notify Group 1" in the android app , i need to send the notification to all the group 1 users. How i implement this logic? I think the same logic is using in the group chat .</p>
  
  <p>Can you provide me the sample code for android and server side?</p>
  
  <p>Thanks..
  Zacharia </p>