Diabetes Detection App for iPhone?

Hello all
My mother-in-law says her friends use some kind of app to detect/monitor diabetes on their iPhones. Is this for real? This might have been a great Apple highlight in an earlier keynote, but I don’t recall it being mentioned.

When I do a search on the App Store, I see several diabetes management apps, but what about detection? I see a few about detection, but how legit are the results?

I would have thought this was more of an Apple Watch thing, but even then, non-conscious detection is something on offer. Can someone clarify or is this an urban myth? thanks.