I'd like to investigate creating a safety feature for Type 1 Diabetics driving a car. Allowing HealthKit glucose data (read from a Dexcom G7 or similar) to be displayed as part of the CarPlay UI background or show an icon/button with the number visible. I'd also like to include a warning system for glucose low's that alerts the driver audibly. Has anyone looked into that before?
Using HealthKit to display data on CarPlay UI
I think you'll struggle here. As I understand it the iPhone is generally locked when in use with CarPlay.
If the iPhone is locked, access to the Health Store database is unavailable. This would mean you couldn't access those blood glucose values.
Yeah, and I’d suggest that you file a feedback report with your use case – If you do so, please share your report ID here. Thanks!
Best,
——
Ziqiao Chen
Worldwide Developer Relations.
A few thoughts here:
If you are running the Dexcom app on your phone, if you look at Apple Health you will find that Dexcom only writes its data to Health with a three-hour delay. It buffers the glucose values internally for display, but they aren't available in Health until they are three hours old. So even if you could read Health (e.g. by keeping the phone unlocked) the data wouldn't be current.
However, with the introduction of widgets in CarPlay in iOS 26, you can achieve essentially what you want with little effort - install the Dexcom widget, and you can display it on the CarPlay screen. There is sometimes a little lag with it updating, but it's much better than nothing.
As for alerts, those are well handled by the phone already, and any low glucose alerts should show up on the CarPlay screen as long as you allow notifications from that app while driving.
Hope this helps!