Windows RT is Microsoft's first OS for ARM processors, which are found in Apple's iPad and most Android tablets. Analysts say RT is targeted at consumers and will attract a new generation of users with little ties to PCs, much like the iPad. The OS will come preinstalled on tablets and differ in some ways from Windows 8, which is considered a successor to previous Windows operating systems.
"People should play with them in the store to see if the device is right for them," said Dean McCarron, principal analyst at Mercury Research. "We have a new device class, a new architecture, and people need to figure out how it fits with their device usage model."
Here are some things to consider when looking at RT tablets:
Windows RT or 8?
Microsoft has engineered Windows RT for touch, Internet connectivity and long battery life, and some tablets highlight those features. Windows RT is viewed as more of a tablet OS in the mold of Apple's iOS, while Windows 8 tablets may appeal to PC users looking for backward application compatibility. The cheapest RT tablet is Microsoft's Surface, which starts at US$499, while Asus' Vivo Tab RT starts at $599.99. Windows 8 tablets are competitive on price, with Acer's new W510 tablet priced at US$499 with an Intel Atom chip code-named Clover Trail.
Application compatibility
With a few exceptions, existing Windows applications will not work on RT. That is partly because ARM processors have not supported major desktop Windows client OSes in the past. But existing applications will work on Windows 8, as previous Windows OSes over the past few decades were written primarily for Intel or Advanced Micro Devices processors. Microsoft is adopting a new application model with Windows RT and 8, and users will be able to download applications through Microsoft's application store, which will show up as a tile in the user interface. "I think that Windows' new app store is ... a move from Microsoft to catch up with the changing distribution channels for software," said Nathalie Lussier, a technology consultant in Brooklyn, New York, who is looking into Windows hardware.
Peripherals and accessory compatibility with Windows RT
A lack of drivers may prevent some older peripherals such as printers or cameras from working with RT. Some device drivers may not have been written to work with RT -- an issue that's similar to existing Windows applications not working with RT. It may be worth checking with device makers to see whether they have drivers for RT. and have published lists of printers that will and won't work with RT.
Memory limit
Windows RT is only 32-bit, which will limit the memory capability of tablets to just 4GB. Windows 8 tablets with Intel's Atom chip code-named Clover Trail will also be only 32-bit, an Intel spokeswoman said. But Windows 8 tablets with Intel's PC-like Core processors are 64-bit, giving devices expanded memory and storage support. Tablets today are adequately served with 32-bit processors, but with usage of demanding applications such as video growing, storage and memory needs will increase in mobile devices. ARM has taken a step ahead by announcing its ARMv8 64-bit architecture, with chips likely appearing in 2014. Microsoft has not announced its 64-bit plans for Windows RT.
ARM processor options
Windows RT tablets have already been announced with chips from Nvidia and Qualcomm, which license ARM processors. Microsoft's Surface, Asus' Vivo Tab RT and Lenovo's IdeaPad Yoga 11 hybrid will have Nvidia's quad-core Tegra 3 processor, which may appeal to gamers and users looking for fast performance. Samsung's Ativ Tab and Dell's XPS 10 will have Qualcomm's dual-core Snapdragon S4, which is designed to balance performance, battery life and connectivity.
Hardware limits
Windows RT tablets will have only USB 2.0 ports, which are slower than the current USB 3.0 port. However, peripherals such as external storage devices with USB 3.0 ports will be able to connect to RT tablets because of backward compatibility with USB 2.0. The peripherals will work only if compatible with Windows RT. USB 3.0 ports will be available in Windows 8 tablets with Intel's Core processors.
Enterprise features
Dell and Samsung have highlighted enterprise features in RT tablets. Dell's XPS 10 tablet can be remotely disabled if lost or stolen, and software images and updates can be remotely pushed to tablets. Dell is also including some security features such as TPM, a hardware-based cryptography and authentication technology. Samsung will include Microsoft Exchange and Cisco VPN (virtual private network) support in Ativ Tab.