To make your WCF service running , follow these steps
1) After creating a WCF Service application, if you hit f5, the service will run in browser.
2)Click on the service name in the list of items displayed in the browser(by default you will be able to see "Service1.svc";
3)Clicking on that link navigates to a page where it shows some text called "You have created a service. bla bla bla". Copy the browser url here. It will be something like this
e.g
http://localhost:16679/Service1.svc[
^]Now leave this project as it is(in running state)
Move to your phone app and add service reference to the running service</pre>
You will be able to access the service