Screen Width
Pixels	%	Width
120 128 132 176 208 240	3   19   3   22   2   9	29mm   29-32     29-39   39   34-36

The Screen resolution size 176 x 220px = 17% of a sample of 239 phones. 240x320, 128x160 and 128x128 = 9% each. (4 resolutions = 45%)
Manufacturers/Retailers quote the screen size in Pixels and not as a physical size ie. 29mm. This going to cause them problems. How can the say that their phones have a High Definition screen if they quote in Pixels.
Screen physical widths differ very little in size (10mm) so the wide range Pixel widths (128 - 240) alter the screen's quality. Samsung D600 screen width is 240px & 47mm = 7.1 px/mm. Compare this with the Samsung Z500 with a screen width of 176px & 45mm = 5.7 px/mm.
Low Definition Screen = 4 px/mm. Standard = 5-6 px/mm. High = 7 px/mm
This effects the size of the displayed Text but this may be compensated by the Manufacturers changing the Default Font size. (Impossible to establish).
The large variation in Pixel Width causes serious problems if you size your Images in Pixels, almost 100% difference between phones. Surprisingly, Pixels are not always square. Worst case found was 0.28 x 0.20, 20% out of square.
Revised 1.1.06

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