The Share contract and the namespace you indicate is only for exchanging data between two Metro style apps on the same machine.
To share data with another machine, you'll need to use some kind of web transport, such as XmlHttpRequest or sockets. For the former, look at the WinJS.xhr helper (http://msdn.microsoft.com/en-us/library/windows/apps/br229787.aspx);
for the latter, look in the Windows.Networking.Sockets namespace (http://msdn.microsoft.com/en-us/library/windows/apps/windows.networking.sockets.aspx). You
can also do background download/uploads with Windows.Networking.BackgroundTransfer (http://msdn.microsoft.com/en-us/library/windows/apps/windows.networking.backgroundtransfer.aspx).
Note that the share contract doesn't automatically provide UI to share data to a web service. You can either do that directly in your app, or, if you want to allow other share source apps to send data to the server, you can implement a share target app on
top of the backend transports. We don't have a sample for this, but it should be relatively straightforward to combine the share target sample (http://code.msdn.microsoft.com/windowsapps/Sharing-Content-Target-App-e2689782)
with some of those below.
Some samples:
XHR:
http://code.msdn.microsoft.com/windowsapps/Navigation-sample-1c34abd1
Stream sockets:
http://code.msdn.microsoft.com/windowsapps/StreamSocket-Sample-8c573931
Web sockets:
http://code.msdn.microsoft.com/windowsapps/Connecting-with-WebSockets-643b10ab
Background transfer:
http://code.msdn.microsoft.com/windowsapps/Background-Transfer-Sample-d7833f61
Also see these tutorials:
Transferring files from a network resource (background transfer)
Connect to peers, web and network service (all the other topics)
.Kraig
