With the Windows 8.1 update, Microsoft is integrating SkyDrive with Windows more deeply than ever. This includes more settings sync, document save integration, camera roll integration, and of course file syncing between the cloud service and your PC or device, handled in a more sophisticated way than ever before. The best news? It all works with Windows RT too.

The initial releases of Windows 8 and RT of course provide basic settings sync functionality. But that was it, and while Windows 8 users can get an add-on SkyDrive desktop application to facilitate file sync with their cloud storage, Windows RT users have no such option.

Now, everything has changed. And it’s a lot better, for both Windows 8 and Windows RT users. Here’s what you get.

Deeper SkyDrive integration. SkyDrive integrates so thoroughly into Windows, it’s now an option during Windows Setup.

View your SkyDrive storage. Via the new SkyDrive settings interface in PC Settings, you can see how much SkyDrive storage space you have and how much you’re using. You can even buy more storage, right from Windows.

Save documents to SkyDrive by default. If you enable SkyDrive integration, you can opt to save files to SkyDrive by default, rather than your Document folder. This way they’ll always be in sync across all your devices.

Camera roll folder. As with Windows Phone, you can optionally choose to automatically upload all of the photos and videos you create with your PC/device’s built-in camera to the Camera Roll folder in SkyDrive, in either good or best quality. It can be configured to behave differently on a metered connection.

Settings sync. As with the initial releases of Windows 8 and RT, you can sync settings between your devices. But now you can backup settings that aren’t synced, and there are more settings to sync, including Start screen settings, installed apps, and app data.

Seamless File Explorer integration. This one is the kicker. When you enable SkyDrive integration, Windows creates a SkyDrive folder in your user profile and populates it with a set of special shortcuts that duplicate the contents of your cloud-based SkyDrive storage. But it doesn’t mindlessly sync everything, an act that would overwhelm the available storage on most tablets. Instead, it just shows you which files are available, and when you’re online, everything works normally. (In fact, file access is shockingly quick.) But if you want to use files offline, just right-click any folder or file and choose Make Available Offline. (You can later reverse it too.)

This enhanced SkyDrive integration is arguably the killer new feature in Windows 8.1, especially for Windows RT users. I’ll be writing more about this new feature soon.