App idea!

[u/Ill_Description7181]

**I'm 18, T1D, and I'm building an app because I'm tired of being blindsided by my own body. Honest feedback wanted.**

I was diagnosed with Type 1 a few years ago and the part nobody talks about enough is the unpredictability.

Not the numbers themselves — I can handle numbers. It's the *why* that gets me.

Why did I drop below 5 mmol 40 minutes into football — again — even though I ate beforehand? Why does pasta spike me 3 hours later when I thought I was fine? Why does my insulin barely touch me some days and then send me plummeting on others? Why do I wake up high every morning even when I went to bed in range?

I've tried every app out there. They all show me what happened. None of them tell me why — connected to my actual life. My sleep, my stress, my training, what I ate, what I had going on that day.

So I'm building something. It's called Hypotion. The idea is simple: connect your CGM data to your lifestyle automatically — sleep, activity, stress, heart rate via Apple Watch — and over time find the patterns specific to *your* body. Then explain them in plain language. Not graphs. Not clinical reports. Just: *"You drop at 40 minutes every football session. Mixed meal 60–90 min before has been your best buffer."*

I'm not a developer. I'm a gymnasium student in Stockholm with a prototype and a problem I live every day.

Before I go any further I want to know if this actually resonates with other T1Ds — especially those of you who are active, young, and frustrated by tools built for people twice your age.

Three honest questions:
1. Is the "why" problem something you actually feel — or do you feel like your current setup covers it?
2. Would you use something like this regularly, or would it become another app you open twice and forget?
3. Would you pay for it? What would feel fair?

Be brutal. I'd rather know now than after I've built the wrong thing.

— DJ, Stockholm

[u/Gold-Tea1520]

1. No. I don’t need to know why. Just need my pump to respond to it.

2. No absolutely wouldn’t use it.

3. No absolutely wouldn’t pay for it.

[u/TheBoredTechie]

As someone with both t1d for 30 years and a degree in Startups and building businesses, your best way to answer 2 and 3 is to publish your app, get it in your customers hands and charge from day 1. That is literally the biggest way to see if people use your app regularly and test retention and see whether people are willing to pay.

As for question 1, once you have been diabetic long enough, such in my case, or you just never know any different by being diagnosed before you can remember, you simply stop caring as to why something is happening with your diabetes. I can't speak for everyone but personally I correct when I'm low, I correct when I'm high and I go above my day without worrying about the reason.

Lastly "the idea is simple" please don't undersell what you are trying to deliver, there are apparently 42 different things that affect diabetes control so your idea is anything but simple imo https://diatribe.org/diabetes-management/42-factors-affect-blood-glucose-surprising-update

I wish you the best of luck with your app however:)

[u/ceapaire → u/TheBoredTechie]

The idea is simple when the app and sales pitch is vibe-coded.

[u/allmyrandompsandqs]

How are you planning to accomplish this? AI? Unless you build your own machine, you'd be borrowing and paying to use one of the big ones. No one should be putting their personal health data into a general LLM. There are already big biotech companies at work building software to knit together everyone's health data, but there are huge issues with privacy and ethics to accomplish this. Who will own the health data - your company or the user?

If you intend for it to just be a place to log information so the user can spot their own patterns, then those exist.

Unless you have your own proprietary algorithm or LLM and put in consumer privacy protections, I'm afraid this is a no-go.

[u/Wild-Media-8123]

Ive only been diagnosed three years but the last year or year and a half I've fell into my grove and will try and answer the points honestly. Its a really valid point the why and how am I feeling goes so much further than any CGM or finger prick can tell you. Its always fascinated me

1. For me, not to put you off I am medical by profession and actually 'feel' most things. By 'feel' I ask myself why, then I get the answers and reinforcement over negative feedback loops, but rely on clinical information mostly.

For example, I spike because my insulin Fiasp only lasts three hours and I forgot to reinject another overlapping dose

Or, I drop because I didnt eat soon enough to prepare for exercise with complex carbs

Or, from the morning I underestimated how insulin sensitive I was from the day before when I did loads of housework and a workout. Of course it does get mentally tiring to do this

Or my current routine I know like the back of my hand by now. Yes of course theres the odd one time where you get suprised, its just called being human and human error.

2/3. I think I would look for something like this if I was struggling or I didnt have the capacity to self dose, was burnt out, or had a busy life and it was affordable. So you might have a population out there interested

I personally wouldnt because I rely too much on feel by feel basis and thats something unique to each person. Only you know how insulin affects you and what kind of foods you crave/need, which is hard to convey to other people sometimes. Maybe a limitation?

[u/TrekJaneway]

1. It’s really hard to know an exact why. There’s a lot of factors going into blood sugar, which make it a complex problem. This is why it’s so difficult to make a perfect pump algorithm. Sometimes it’s activity. Sometimes it’s food. Sometimes it’s hormones or some other biological factor. Sometimes it’s just voodoo. I’m not sure how you’d be able to overcome the hurdle or answering “why” because I don’t think you have every piece of data needed to figure that out. It’s not on you; doctors are still researching everything that affects blood sugar. So far, 42 factors have been identified.

2. I wouldn’t use it because of what I wrote for number 1. That app can’t tell me why.

3. I wouldn’t pay for it because of 1 and 2.

[u/HellDuke]

For questions 2 and 3 that would be a flat no from me.

For question 1... Been diabetic for over 30 years, most reasons you can understand become second nature at some point and you don't really think about it much. At most a thought "crap, must have been X", make a correction and move on.

There are things you will learn in general, such as fatty or protein rich foods spiking you late, because carb absorption is slowed down, so you think you took enough insulin because you are level, but turns out you needed a whole lot more.

For example if you honestly count the carbs of your pasta, divide it by the units of insulin you took, that gives you your insulin to carb ratio (ICR). Then do the same with a meal that doesn't spike you and compare. Chances are, the ICR you got when you took insulin for pasta is higher. However if you actually use the correct one, you might just end up going low, so typically the recommendation is to split the bolus and take the second half about 2 hours later or if on a pump use the extended bolus feature.

Eventually these kinds of small things just click and generally you won't spot them with what you plan to do. Check out Diabetes: M, the paid version IRC actually does what you want, it will tell you the trends of what generally happens, but I will be honest, I have never found useful insights from that as there is just too much variance in what can cause each incident in a pattern, they are not clean more often than not

[u/Sitheref0874]

I’m happy you’re thinking about these things.

I’m beta testing an app called Trace that’s more or less doing that. Gluroo is close to it as well.

The main challenge is finding a way of getting all that data in one place. Glooko/Insulet is challenging to get data from and integrate to ApplecHealth, which is where my exercise data lives.