Hi, my name is Phil. I am a 32-year old product designer working in Berlin for a Start-Up that is building intelligent conversation software.

I was diagnosed with Diabetes Type-1 two years ago and I have been using the Dexcom G5 Mobile for one year now. Being a UI/UX Designer and simultaneously an end-user of this product naturally, I came across some design and user experience issues that I think could be addressed.

What is Diabetes Type-1?

Briefly explained, your body stops producing insulin resulting in high blood sugar levels. (Wiki)

What is the Dexcom G5 Mobile?

It is a continuous glucose monitoring system for diabetes management.

How does it work?

A sensor attached to your body reads your glucose levels every 5 minutes and sends the data to your smartphone. Based on this data the App shows your current glucose values and trends throughout the day. It is able to warn you if you drop out of a certain glucose range set by you and the system. This is pretty helpful to prevent hypoglycemia or hyperglycemia.

Hypoglycemia

This means blood sugar decreases to below normal levels (measured in mg/dL). Your head becomes dizzy, your body feels shaky and in the worst case you lose consciousness.

Recommended action: eat sugar (fast carbohydrates) to push your glucose level upwards.

Hyperglycemia

It’s basically the other way around, meaning above the normal glucose levels. In contrast to hypo (short form), the danger lies in the long term caused by sequelae (secondary diseases).

Recommended action: inject insulin to decrease your glucose level.

So diabetics want to stay in the “perfect range”.

First things first: I love the G5. It brought a lot of comfort back to my life and made so many things much easier. I cannot say enough how much I appreciate using this product.

Here it comes: But..!

For me and some other fellows I spoke with before addressing this matter to you, the core value of the product is probably a bit different from the original company vision. Let’s take a look at Dexcom’s main screen:

At the top we have a burger-menu-icon and some other shortcuts (not important for now).

The main screen’s attention displays my current glucose value and trend. (Center of the screen)

At the bottom we can see a trend graph of my glucose levels during the last hours. The precise values are somewhat hard to make out, but in general I can see if my values have been within the optimal range.

In general, the goal for type 1 diabetics like me is to keep my glucose level in between a certain range. More precisely: from 80mg/dL to 140mg/dL.

Less usage of the App is a good thing!

What actually makes it so cool is that there is no need to open the App when you are in a good glucose range. Managing diabetes sometimes can feel like a full-time job and you just want to forget about it. That is where the alert-system comes in handy. It lets you forget about it, as long as everything is fine. No need to stress the user. It stays in the background and only seeks my attention when necessary. If something comes up though, the information needs to be crystal clear.

The only thing which has not been considered in the user experience design is that diverse activities during the day require different sets of alert thresholds.

Why different thresholds are important

It’s quite normal for your glucose level to start rising after lunch, even if you managed your insulin rate correctly. It usually rises above the critical level for a short period of time before it goes down again. This is due to the fact that carbohydrates are sometimes processed faster in your body than the insulin. But don’t panic — no need to correct with another insulin dose, it will just take some more time after the glucose level falls back into the correct range again.

However, how does this affect the user experience? For me that means that 40–60 minutes after lunch my smartphone starts beeping like crazy when I am likely to be in meetings or discussions with my colleagues at work. Yes, that is what the app is supposed to do, but I know beforehand that my levels will go down by itself anyway. So what is my reaction to the alarm notification? I turn the alarm off or lower the threshold beforehand. In result this proves to be annoying because for me taking this action is more or less redundant.

Let’s take a look at three high and low thresholds I use quite often: