[Nexus One General] flarbear:
OK, I checked that out. For what it's worth, that app is printing out the resolution in DIP - device independent pixels - which is a scaled version of the true resolution in physical pixels. You can read more about the unit here (note that they are also referred to as "density independent pixels"):

http://developer.android.com/guide/practices/screens_support.html

That is likely true, but you have to understand the answer it is returning. It is not returning the number of physical pixels that the OS uses when it renders to the screen, it is returning the virtual units it uses to express the size of things. The app knows this which is why it specifically prints "device independent pixels" on the screen with the result. It is not returning the number of pixels used to render the graphics, though.

This does affect, as you later point out, the size of elements on the screen, mainly for apps that rely on the default DIP units and don't take steps to either choose to adjust the size of their elements based on the density or choose to set a different coordinate transform so that their units refer to physical pixels.

But it does not affect the quality with which they are rendered. Originally I thought you might be suggesting that elements are rendered with lower quality but now I think you are simply wanting to use more real estate as you later mentioned:

Yes, I agree that they should let the user tune the size of the UI elements if they are willing to deal with being more careful about picking and if they have good eyesight and especially if the user has a higher resolution device which can render smaller elements with a similar level of quality.

BTW, "DPI" is a loaded term. It can mean "the number of rendered pixels per inch" or it can mean "the number of application coordinates per inch" or a number of other measurements. Since this is a thread dealing with the ability of the phone to produce quality images I assumed you may be suggesting that the quality problems are due to the phone not using every pixel when it renders - in effect rendering everything with only 320x533 actual pixels in an off-screen buffer and then stretching that buffered result to fill the real estate of the screen. Note that this is what the iPad appeared to be doing for many of the iTunes apps in the demos and is a viable technique to use for apps that believe not only that "320 units" spans the screen, but also that they can reach out and touch those 320 pixels and play with them. If you render such an app with more pixels then it might be OK if it only ever tells the OS what to render and how big to make it and never asks to read back the pixels for instance, but it won't work if they ever perform an operation which requires you to tell them what pixels are in their window. The drawback of that technique is that the app will look fuzzy as a result of the pixel scaling. I don't believe that Android uses that technique, though - it looks like they use coordinate scaling, not pixel scaling, for legacy apps. They especially do not use pixel scaling for the home screen from what I've seen.

So, yes, I agree that it would be useful for Android to provide a setting to customize the size of the UI elements and that setting would be more useful on higher DPI phones, but that has nothing to do with whether the 320x533 DIP default on this phone affects the quality of the graphics rendered as per the discussion on this thread.