Of course, take any of these patent applications with a generous pinch of salt -- we haven't seen an Apple stylus yet, for example -- but perhaps this is the reason Apple bought fingerprint sensor maker AuthenTec back in July.

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While AuthenTec is known best for its fingerprint-sensor chips, it also has a number of security products.

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Art Stewart, vice president of wireless products at sensor maker AuthenTec, which provided fingerprint sensors for the phone, says LG had "antenna issues" with the device.

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