Apple could be developing a new wearable device even smaller than the Apple Watch: an Apple ring.

That is, if a recently filed patent leads to an actual product.

The ring, which could be made with or without a touch display, would be linked to a larger device such as an iPhone, according to the patent filing.

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Rendering of a proposed Apple smart ring from a patent application recently published by the U.S. Patent & Trademark Office.
Source: Apple via U.S. Patent & Trademark Office

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Rings with a touch display would be worn on the index finger and be controlled with the thumb, according to the patent application.

Apple files many patent applications and is frequently granted patents without those proposed products actually making it into consumers' hands.

Apple didn't immediately respond to requests for comment on plans to sell a smart ring.