A former Googler is working on an Apple Watch accessory that could actually save lives

The Apple Watch has a built-in heart rate monitor, but some people need a medical-grade electrocardiogram, the gold standard for heart rhythm monitoring.

AliveCor, a company headed by former Google executive Vic Gundrota, is building an EKG that fits into an Apple Watch band. Kardia Band is not a toy or a fitness band, Gundotra tells Recode. Instead, it's a full medical device with expected FDA approval. 

According to AliveCor, users can record their heart rhythm in 30 seconds by touching the band's integrated sensor. If the band detects an elevated risk of stroke, it can send a note to the user's doctor through an associated app that runs on their iPhone. 

One big question facing the Apple Watch in its first year is whether its health features would require FDA approval. Apple held a meeting with FDA officials before the Apple Watch was released to find out exactly where that line was. 

Ultimately, Apple apparently thinks that FDA regulation would be a load of trouble, and specifically angled and marketed the Apple Watch to avoid regulation and scrutiny. But AliveCor shows that accessory makers may be willing to take up the slack. Gundrota tells Recode that he believes it's the first FDA-cleared smartwatch accessory. 

The fact that the Kardia Band can contact a doctor means that it's technically a medical device, according to guidelines recently updated by the Food and Drug Administration. 

The FDA has not yet cleared the Kardia Band, although a similar AliveCor product for the iPhone is currently on sale for $99, and the government has approved the algorithm for analyzing the EKG data from the band. 

Last fall, 9to5Mac reported the Kardia Band was expected to sell for around $199. AliveCor believes it will go on sale in "late spring."