The display colours are as they are due to display RGB primary calibration at the factory - and software to a much much tinier degree - nothing to do with manufacturing. It is either intentional to circumvent other problems or simply poor-to-no calibration. The DDI approximation won't by itself make such errors with proper display calibration.
1. The Desire and Nexus One both have a very blue colour temperature intentionally, which shifts the greys to the red-magenta spectrum when combined with the PenTile over-green subpixel approximations the DDI must provide for. The reason for that starts with the fact that the organic B element in OLEDs fail far faster than the RG, and the blue luminance is very low but with high power draw which results in very low blue luminous efficiency right from the start. This is a known problem with OLED engineering. To delay the onset of the B spectra output decreasing to the viewer, manufacturers intentionally shift the beginning calibration towards very blue output. So it starts off with colour oversaturation and a bluey temperature with higher power draw, but as the B pixels degrade and their luminosity decreases, the blue doesn't suddenly disappear within the first 2-5 years of average use, it will just decrease significantly. As the blue luminance decreases, at some point, the colours will appear far better than when new.
You can see such measurements in these tests by professionals, for instance: http://www.displaymate.com/Nexus_One_ShootOut.htm
2. There are other workarounds employed, like the PenTile matrix, but it shouldn't affect the image reproduction much if the display is properly factory calibrated with the primaries and the software algorithms are decent with scaling and compression. Higher B spectra than with PenTile would increase sharpness but also increase power by a large margin on these displays too. Increasing B spectra would also increase the probability of defective subpixels on the display.
3. The bad readability people complain about in sunlight is due to very low maximal white luminance with these OLED displays (~200*cd/m2) and the high reflectance on these displays (primarily because of the metallic cathode, large spaces between layers so the panel is far down and poor anti-reflective coating on-screen). The device manufacturers can easily circumvent these, with additional time+cost.
4. If colour accuracy is what you are after, except black, nothing on the market touches the LCD featuring Droid X and the Droid - both known for absolutely excellent colour reproduction. I've used both. Look at the Droid here, for instance: http://www.displaymate.com/Motorola_Droid_ShootOut.htm
5. Just to be clear. I have absolutely no problem with some bits currently appearing slightly pink instead of light grey. Had someone here not complained, I wouldn't have noticed. I do dislike the obvious oversaturation in colours everywhere much though.
- Sent via my HTC Desire -