Does the "Supporting Multiple Screens" document contradict itself?

Question

In the Supporting Multiple Screens document in the Android Dev Guide, some example screen configurations are given. One of them states that the small-ldpi designation is given to QVGA (240x320) screens with a physical size of 2.6"-3.0". According to this DPI calculator, a 2.8" QVGA display equates to 143 dpi. However, further down the page the document explicitly states that all screens over 140 dpi are considered "medium" density.

So which is it, ldpi or mdpi? Is this a mistake? Does anyone know what the HTC Tattoo or similar device actually reports? I don't have access to any devices like this.

Also, with the recent publishing of this document, I'm glad to see we finally have an explicit statement of the exact DPI ranges of the three density categories. But why haven't we been given the same for the small, medium, and large screen size categories? I'd like to know the exact ranges for all these.

Thanks in advance for your help!

Answer 1

So which is it, ldpi or mdpi?

ldpi, at least for the HTC Tattoo, using DensityMetrics and its densityDpi field.

Is this a mistake?

At minimum, it is unclear.

But why haven't we been given the same for the small, medium, and large screen size categories?

DPI is for density. Density has nothing to do with size. Ergo, there cannot be DPI ranges for size.

Table 1 shows size buckets in inches compared to labels (small, normal, large).