title: Mobile Chat application on Google App Engine and Socket.IO
body: <p>I am creating a chat application with Node.JS's Socket.IO and there is a couple things I need clarification on.</p>
  
  <p>I am implementing offline messaging in my app meaning that when a user opens the app he will receive all the messages he missed when they were online. </p>
  
  <p>This is my approach:</p>
  
  <p>1) Client opens the app and is subscribed/joins a room 
  2) The client sends a message to Socket.IO
  3) Socket.IO inserts the message in some kind of database/datastore
  4) When client tries to retrieve the messages it is pulled from the database/datastore and saved on the users phone then it is deleted from the database.</p>
  
  <p>Is this a correct approach?</p>
  
  <p>I was looking at online and some people suggested using task/message queues like Google App Engines Task Queue but I am not sure how this works.</p>