Glucose on my wrist, part 1: The Apple Watch

Bottom line first: Medtronic Mobile on the Apple Watch Series 3 does not work well.

I've had type 1 diabetes for something like 15 years, and I recently decided to try to get my glucose levels displayed on a wristwatch. It seems much more convenient than checking my pump, which is not always easily available, especially in the winter when it's hidden under layers of clothes.

I generally dislike smartwatches but I'm making an exception for this.

This is my first attempt. I expect this to become a series of posts as I iterate towards something I'm content with.

I use a

• MiniMed 780G insulin pump and
• Guardian 4 glucose sensors.

The official MiniMed Mobile app is annoyingly not supported on my phone (Zenfone 8), so I bought a secondhand

• iPhone 7 (2016) and an
• Apple Watch Series 3 (2017)

for this project. The Apple Watch is the only smartwatch that Medtronic officially supports, so I thought I'd start there. I'm aware that many other smartwatches can be used.

You get a warning when you first start the watch app:

Here's what the app itself looks like:

You can also swipe sideways for a graph view:

So how does it work? Not well. The watch app does not refresh properly, and needs to be restarted often. Even then it does not always properly update. Displaying the glucose level as a "complication" on the main watchface is possible, but has even worse refresh issues. (I don't mind keeping the app open, since I only use the watch to check glucose.)

I guess this is the slower performance that I might experience. Maybe a newer Apple Watch would be better. I might try that, but this one is a very nice small 38 mm size, which isn't available on newer models. But it seems you can get new watches in 40 mm sizes however, and that sounds fine.

For this setup, the communication network is pretty reasonable:

It would be neat if I could drop the iPhone and just have the pump send data directly to the watch, but as far as I know that's not possible.

Next up: Same watch, different app!