Apple Watch Series 4 EKG tech got FDA clearance less than 24 hours before reveal

The electrocardiogram feature in the Apple Watch Series 4 got clearance from the U.S. Food and Drug Administration just a day prior to Apple's Sept. 12 press event, reportedly causing some stress at the company.

The FDA's classification letters to Apple were dated Sept. 11, Fast Company noted on Tuesday. The site added that just after the Sept. 12 press event, it overheard an Apple worker talking about the close timing "in exasperated tones" outside the Steve Jobs Theater.

Had the clearance not been granted, Apple might have had to radically revise COO Jeff Williams' presentation on Sept. 12, in which the EKG technology and its FDA clearance were front and center. Williams claimed that the Series 4 is the "the first EKG product offered over the counter directly to consumers."

Similar technology is already in use by AliveCor, which markets the KardiaBand accessory for Apple Watch. The company reached out to AppleInsider to note that KardiaBand was first to receive over-the-counter FDA clearance in 2014, three years prior to wide general release in November 2017. As CNBC reporter Christina Farr explained in a tweet, however, users must have their first ECG reviewed by a doctor in order to "unlock," or view, the reading.

AliveCor details the process on its website, saying that "due to regulatory necessity, new U.S. accounts are required to have their first EKG reviewed by a U.S. board-certified cardiologist free of charge (a $19 value within the app)."

The Apple Watch, on the other hand, has FDA clearance to show its first ECG to users without a doctor review.

The FDA has technically only cleared an "Irregular Rhythm Notifcation Feature" and EKG software that can detect signs of arrythmias. The FDA wrote that the Watch's EKG feature "is not intended to provide a diagnosis," and "not intended for use by people under 22 years old."

Indeed the Series 4 won't even ship with the EKG app installed when it launches on Sept 21. That's coming in an over-the-air update before the end of 2018.

Apple was likely eager to tout the feature in advance however as a way of differentiating its product not just from rivals like Garmin and Fitbit, but earlier Watch models, since the biggest upgrade is otherwise a slightly larger screen.