title: How can i design tcp messages listener in my Android client?
body: <p>i'm a newbie for Android.
  I'm working on a client(android)-server(java) arcitecture application for my project. I have questions..
  My 4-5 activities will send tcp messages to server and get response to do something to their own. So i need a background listener for these messages and then do something in these 4-5 activities. Where can i implement this listener thread to response my different actitivies. Is  it a good way to write 5 AsyncTask in subclass of these Activites to messaging Server?
  I think 1 thread can do the work; but how can i bind the activites..
  Is it the service that im talking about? But i dont want to do something when my app destroys.</p>