Display resolution of a digital television, computer monitor, tablet, smartphone or display device is the number of distinct pixels in each dimension that can be displayed. Development of applications and the changes in monitor pixel density have been under great speculation. Until recently most monitors typically had a pixel density* of 96 ppi. Various different company’s monitors were designed to match the display size (inch size) with the resolution, therefore most OS and applications were also made based on this 96 dpi standard. physically smaller monitor or smartphone requires physically fewer pixels to remain usable at HiDPI.

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Since Vista, Windows has gradually improved HiDPI support of its operating system and development platforms (multi-monitor support was introduced with Windows 8.1). However, there are still many apps that are not or are not fully supported for the following reasons. In these cases, the operating system forcibly zooms in / out of an application created in the usual way above, making it blurry. Also, some apps appear blur-free, but the screen size is small.