With the sets of basic specifications and features set in stone, HTC's engineers can then offer the right phone sizes that meet the carriers' requirements, as well as showing a relatively bland rectangular ABS block as an indication on how much space is needed to pack all the components.

ENGADGET: HTC talks smartphone design: from inception to final product

There was a time when smartphones were determined by specifications, but in recent years the basic numbers have remained the same.

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