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iPhone 4S distinguishes itself with an antenna positioned above the Mute button, while the absence of an antenna near the headphone jack sets it apart from the iPhone 4.
On the right side, iPhone 4S features an antenna along the edge, a distinctive trait absent in the iPhone 4.
By leveraging both theory and visual cues, effortlessly differentiate between the iPhone 4 and iPhone 4S at a glance without extensive checks.
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