[Capability usage] There are two capabilities that provide different levels of access to the Internet and public networks. These capabilities grant different access depending on if the app is running on Windows or Windows Phone. On Windows, the internetClient capability indicates that apps can receive incoming data from the Internet. Cannot act as a server. No local network access. On Windows, the internetClientServer capability indicates that apps can receive incoming data from the Internet. Can act as a server. No local network access. On Windows Phone, the internetClient capability indicates that apps have full local and Internet access and can act as a server. Inbound access to critical ports is always blocked. On Windows Phone, the internetClientServer capability indicates that apps have full local and Internet access and can act as a server. Inbound access to critical ports is always blocked. On Windows, most apps that have a web service component will use internetClient. Apps that enable peer-to-peer (P2P) scenarios where the app needs to listen for incoming network connections should use internetClientServer. The internetClientServer capability includes the access that the internetClient capability provides, so you don't need to specify internetClient when you specify internetClientServer. Note Windows Phone Store apps have a single network capability that enables all network access for the app. The internetClientServer capability enables complete access to the network for both client operations (outbound access) and server operations (inbound access). However, if any of the network capabilities (internetClient, internetClientServer, or privateNetworkClientServer) are specified in the Package.appxmanifest file, a Windows Phone Store app has complete access to the network at run time for both client and server operations. While you’re developing and testing your Windows Phone Store app app in Visual Studio, you get the networking capability (Internet (Client & Server)) when you run the app, even if you haven’t specified this capability in the app manifest file. When you publish your app, however, your app does not automatically get the networking capability. Make sure you check the Internet (Client & Server) capability on the Capabilities page of Manifest Designer if your app requires network connectivity. [Capability scenario] 
Internet and public networks