The operating system on the Surface RT is Windows RT, which is essentially Microsoft's Windows 8 PC operating system (OS) but ported to run on ARM-based processors in order to deliver a thinner and lighter tablet with longer battery life.
As detailed in our review of Windows 8, the OS comes with a number of built-in apps, including Mail and Calendar tools, Messaging, Maps and others.
We were able to link the built-in Mail and Calendar apps to our corporate Exchange account and thus keep in touch with work while testing, while the Messaging app similarly integrates with Windows Live Messenger.
There is also the Windows Store, which already seems to contain a number of Windows RT apps that can be directly installed, including a free Skype app, Twitter clients, games, and a variety of others.
Although Microsoft claims that more apps are being developed to run on Windows RT, the number of apps available is still limited and there are far fewer in the Windows Store than are available in Apple's App Store for Ipad tablets or in the Google Play store for Android tablets.
There are differences between the two versions of the Windows OS, with the most significant being that the Surface RT with Windows RT cannot run standard Windows PC applications, as mentioned earlier. Unfortunately, this means that the Surface RT doesn't support the vast range of third-party software applications that have been developed for Windows PCs over many years.
Windows RT also does not include either Windows Media Player or Windows Media Center, and both Windows Update and Windows Defender are set to be always on, settings that cannot be changed.
Microsoft's reason for the latter is that it helps keep your device up to date and secure, but our experience with Windows Update is that it will attempt to install updates at the most inconvenient moment, such as when the batteries are about to run down or just when you want to shut down your system in order to leave for an urgent appointment. We would definitely like to see an option added to manually control when updates happen.
Windows RT is also restricted to printer drivers that are built into the operating system, whereas Windows 8 still supports legacy drivers created for older versions of Windows. Also, Windows RT does not support input using a digital stylus.
Much of the rest of Windows RT is almost indistinguishable from Windows 8, even down to the desktop environment that resembles the user interface of Windows 7. Although you cannot run "legacy" Windows PC applications or any third-party software here, this desktop environment is still supported for functions such as file management and also because many settings are only accessible via the old Windows Control Panel.
The Windows RT desktop also has its own version of Microsoft's Internet Explorer (IE 10) web browser, but unlike Windows 8, this version does not support plugins. Both it and the "Metro style" version of IE 10 have built-in support for content that requires Adobe Flash, but this is restricted to websites contained in a Microsoft whitelist.
We tested this, and found that Flash content displays on The INQUIRER and other popular websites that you would expect to be supported, although not every website will be shown in all its glory. How much this matters is debatable, as there is a general move away from plugins towards active content based on HTML5.
In fact, the whole experience of Windows RT is more appliance-like than with earlier versions of Windows and even Windows 8, bringing it somewhat closer to other tablet operating systems such as Google's Android and Apple's IOS.