Apple claims that its Retina display is as clear as the human eye is capable of seeing. Microsoft says that its Windows 8 Tablets will also be as sharp as the Retina display as its operating system supports a 10.1-inch tablet screen with 291 pixels per inch resolution as compared to the new iPad with 265 ppi.
However, since Microsoft doesn’t build its own hardware, it doesn’t demand that tablet screens or any other screen meet a single requirement as Apple can with the iPad. Therefore, Windows 8 calls for three standard scaling percentages that ensure applications written for the operating system are functional and attractive no matter what size screen they are on, so long as they meet the minimum display specs.
The minimum requirement is 1024 by 768 to allow more layouts to fall in line with most website resolutions and the devices that most Windows 7 users already have.
As pixel densities increase, the size of each pixel gets smaller and so if no accommodation is made for this change, objects and type sizes in apps would shrink as the screen resolution gets better. And so,scaling percentages ensure that as display resolution increases, the actual size of the objects remains within a usable range.
Those percentages are 100 percent, 140 percent and 180 percent. If developers write applications to accommodate them, the apps should look good no matter what type of device they run on so long as the devices meet Windows 8 minimum display requirements.
Microsoft has frameworks of standard pixel units and XAML layouts so developers don’t have to manually code the apps to scale. Images corresponding to each scaling percentage can be stored and appropriately named so the appropriate one for the hardware will be chosen automatically.