Both Aspire S3, UX31 and MacBook Air have an aluminum alloy shell.
The latest rumors suggest that ultrabook may be inadequate due to the lack of aluminum supply.
All three models have a thin front edge of 3 mm. The top-down order includes MacBook Air, Aspire S3 and UX31.
Left edge of all three machines. The MacBook Air and UX31 both have USB ports, while the Aspire only has a 3.5mm headphone jack.
UX31 is the only model equipped with USB 3.0 port on the right side.
Unlike the two competitors, the Aspire S3 is equipped with USB 3.0, 2.0 and HDMI ports on the back. HDMI is also an adversary's advantage from Acer.
Aspire S3 and MacBook Air are all rounded at the edges while the UX31 is more square (bottom).
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The trio all have 13-inch screens.
Chiclet-style keyboard.
The Aspire S3 on the left has a slightly smaller touchpad than the UX31.
S3 keyboard with plastic while UX31 is metal.
The underside of UX31 (upper) and S3 below.
S3 compared with UX3 (below).
the underside of all three models.