updated README

README.md

@@ -3,6 +3,15 @@ Using Celery with Flask
 
 This repository contains the example code for my blog article [Using Celery with Flask](http://blog.miguelgrinberg.com/post/using-celery-with-flask).
 
+The application provides two examples of background tasks using Celery:
+
+- Example 1 sends emails asynchronously.
+- Example 2 launches one or more asynchronous jobs and shows progress updates in the web page.
+
+Here is a screenshot of this application:
+
+<center><img src="http://blog.miguelgrinberg.com/static/images/flask-celery.png"></center>
+
 Quick Setup
 -----------