Bitesized tidbits for building Modern (Metro) apps.
With Windows Phone 7, there was no way to be able to debug your app for when there might be no network connection. All you could do was Build > Deploy > Pray. With the release of the Windows Phone 8 SDK, that’s now changed.
Load your WP7 or WP8 project into Visual Studio 2012, choose one of the Windows Phone 8 emulators, then click Tools > Simulation Dashboard and check the Enable Network Simulation checkbox. If the emulator you chose isn’t already running, it will run it for you.
From here, you choose the quality and speed of network, which includes No Network as an options.
Worth noting this simulation dashboard also lets you simulate reminders.