Surface has a 3-millimeter-thick detachable cover ($100) that doubles as a keyboard and connects to the main body of the tablet via a magnetic hinge. iPads have similarly attached covers, but that's all they are -- covers. You can buy third-party keyboards (typically $150), but they don’t attach and aren’t as thin. The Surface Touch Cover keyboard has no mechanical keys, but the areas marked as keys are touch sensitive, and Microsoft claims they respond more quickly to taps than a traditional keyboard. A second version of the keyboard called Type Cover does have mechanical keys and is 5 mm thick. Microsoft claims that it, too, responds faster to touches. The covers come in orange, aqua, pink, and black.