Metro apps
Metro apps are touch-screen-friendly apps written especially for Microsoft's WinRT programming interfaces.
ARM-based Windows RT devices, such as the Surface tablet, will require Metro apps. Devices running Windows 8 are expected to be able to run both Metro apps and Win32 apps.
Metro apps, which will be sold in an online store much like the Apple app and Android Google Play stores, are expected to sell for $1.49 and up. The name Metro, which is the name of a design language originally conceived for mobile Internet devices (MID) and smartphones, may not be associated with the apps when they come to market. Microsoft has said that the name "Metro" may remain an internal code name used by developers. It is not yet clear what the customer-facing name for Windows RT apps will be.