Terms Screen size, density, density independent pixel, resolution as a picture – pictogram.
Test your knowledge
Q: How to find out the phone screen size?
A: (By length of display diagonale in inch – Not to measure a diagonal of device!!!)
Q: What resolution has 720 x 1280 display?
A: (921600 pixels)
Q: What does it mean “240 dpi” screen density?
A: (Display have density 240 x 240 dots – “Tri-color LED etc.” – per every physical (real) square inch. If you have icon 240×240 pixels, this will just occupy an area of one square inch on the display.)
Q: Phone have screen density 240 dpi. Image for 160 dpi screen density have size 128x 128 pixels. What will be the size of the image for 240 dpi screen density?
A: (Calculate the virtual pixels size. 128 * (240/160) = 192. You have to resize image to new size 192 x 192 physical pixels and put into folder drawable-hdpi (high) ~240dpi for phone with screen density 240 dpi. ) or use density independend pixels 128dp x 128dp.