The Apple Watch is about to get a lot more useful with bands you can swap out to track health symptoms

Key Points
  • The Apple Watch will link wirelessly to a glucose sensor from Dexcom, a medical device maker, Apple announced at WWDC.
  • Dexcom stock spiked more than 6% on the news.
  • Developers expect swappable watch bands laden with sensors to track health symptoms.
Apple Watch to allow glucose data pulling from Dexcom
Apple Watch to allow glucose data pulling from Dexcom

Apple will release a new bluetooth API for Apple Watch, its heath and fitness-tracking smartwatch. The company's vice-president of technology Kevin Lynch said at the company's annual developer conference that users would be able to link their watch to a glucose sensor from Dexcom, a medical device maker.

Dexcom's stock spiked more than 6% in the wake of the news.

Health developers say this is a promising sign that Apple will open up new pathways for them to create their own interchangeable watch bands laden with health sensors. Brandon Ballinger, founder of Cardiogram, a health-tracking app for Apple Watch, said it's exactly what developers need to do just that. "This new bluetooth API may seem like a small detail, but with it, Apple is laying the right technical foundation," he explained.

Previously, Ballinger said, developers building health sensors would need to communicate with the iPhone over Bluetooth — but not with Apple Watch. "So data may have been lost if the phone was out of range," he said — and that's a big problem for health conditions that would benefit from continuous tracking.

Health startups are already building watch bands that use sophisticated sensors to track health conditions.

A startup called AliveCor announced in 2016 that it is developing a Apple Watch band called Kardia to track electrocardiograms. The goal is to detect abnormal heart rhythms, called Atrial Fibrillations, via the watch. Such irregularities can result in a stroke and other potentially fatal outcomes. AliveCor is still awaiting clearance from the U.S. Food and Drug Administration before bringing its watch band to market.