Apple Inc. is developing an advanced heart-monitoring feature for future versions of its smartwatch, part of a broader push by the company to turn what was once a luxury fashion accessory into a serious medical device, according to people familiar with the plan.

This is one of those rumors that I would put in the “makes sense” category. Apple has redefined how we track health on our watches in the last few years. If they are able to add a reliable EKG to the watch, it would seem to fit into the company’s larger plan of enabling its users to track health and fitness.