“The U.S. Patent and Trademark Office on Tuesday issued Apple U.S. Patent No. 9,142,925 for a ‘D-shaped connector’ that replaces the existing low-profile headphone plug and receptacle standard with a shorter, thinner design,” Campbell reports. “This ‘improved’ model would sport all the functionality of a modern 3.5mm TRRS (tip, ring, ring, sleeve) connector, but with a trim profile suitable for use in extremely thin devices.”

“Taking on a ‘D’ profile, Apple’s plug has one flat side that acts as a keyed feature, meaning it restricts insertion to a matching D-shaped cavity,” Campbell reports. “Apple could bypass TRRS designs altogether and introduce a Lightning-connected headphone, but that would prohibit simultaneous charging. It remains to be seen what Apple has planned, but if its portable device designs get much thinner, the demise of the 3.5mm plug is a near certainty.”