title: Messages in Mqtt Android
body: <p>I have a scenario in which Sender send a message on a topic. But there is a client which was never connected previously at all, connect and subscribe to same topic. How can he receive all the messages previously present on that topic for newly connected client. </p>
  
  <p>I used cleanSession = false nothing happens</p>
  
  <p>I used the Retained message = true. Then only last message is recieved.</p>