title: Android Connectivity to PC
body: <p>I have a <code>C#</code> application on PC which regularly backs up data to a server.</p>
  
  <p>I am now starting the development of an android app which I am hoping to display the same data as held on the PC and server. Having never done any android development before, I am investigating what is possible with android.</p>
  
  <p>Would it be possible to send data to/from an android device directly to an application running on a PC, or would this need to go via a server?</p>
  
  <p>Also, is it possible for an android app to send/receive data without the app being open? For example, the facebook app seems give me notifications even if it is closed.</p>