Show HN: Meetrics – Track anything, correlate anything, ask your data questions

Last year I was diagnosed with cancer. In between the shock and the treatment plans, I found myself drowning in numbers — blood test results, biomarker levels, medication schedules, daily pain scores, fatigue ratings. My oncologist needed to see trends. I needed to understand what was happening to my body. And no app I tried could handle what I actually needed to track. Health apps wanted me to log steps and water intake. Spreadsheets worked but were miserable on a phone. What I wanted was dead simple: let me log any number, with any tag, at any time, and then show me what's happening over time. So I built it. Meetrics is a personal metrics tracker. You define what matters — there are no pre-built categories or onboarding wizards asking about your fitness goals. You just log values with tags. In my case, my tags look like this: cea — a cancer biomarker from my blood workldh — another cancer biomarkerpain — daily score, 1-10fatigue — daily score, 1-10wbc — white blood cell count, an immune system indicatorhgb - hemoglobin, helps get oxygen to cellsrbc - red blood cell counttook_medication_x — yes/no (or how many), logged dailybowel_movements — on account of it being colorectal cancerwater — water intake, logged daily- Plus automatic imports from Apple Health: steps, heart rate, sleep That's the Feed tab. Tap +, pick a tag, enter a value, done. It takes about three seconds to log something. Over weeks and months, those three-second entries turn into something genuinely useful. You can also backfill data which I did for the available tp me test data. The Analytics tab is where the data starts talking. You can view any tag over time as a line chart, toggle a rolling average to smooth out day-to-day noise, or enable a 2σ filter to strip outliers that would skew the picture. But the feature that changed how I talk to my oncologist is the Correlate tab. You pick any two tags and Meetrics calculates the correlation between them — with an adjustable time lag. For example, I found a meaningful correlation between my chemo and its side-effects which was surprising because the side-effects did not happen when thee doctors said they would but later. I showed this to my oncologist on my phone during an appointment. Instead of me trying to describe "I think the side-effects come much later than you warned," I had a chart that showed exactly that with a max correlation at an 8 day lag. It changed the conversation. Recently, I had positive results on my latest CT scan. All of my tumors had shrunk compared to the previous scan. This is in sharp contrast to my previous scans which either showed stable sizes or even slight growth - despite being on chemo for months. I haven't figured out how to log this yet because the CT scans don't provide tumor UUIDs ;-). My current mission is to figure out what made this last month different from the previous months. Perhaps it was the slight improvement in my glucose readings (I am also a T1 diabetic). Although the downward trend looks very weak. In any case I know that I need to keep it lower. Ever since I started chemo, it has seemed to me that keeping my glucose in control has been much more difficult. Although the data shows otherwise (note that I have been on chemo for 5 months and below I'm showing 1Y): What has ticked up is my walking and this one is a known predictor of cancer survival. Below is my steps for the last 3 months which has an obvious upward trajectory (note that the previous scan was about 6 weeks before the one this week): And the sharp increase in walking is in part due to the weather improving and in part because my puppy was not able to be walked outside until mid February due to vaccine stuff. My puppy was not able to be walked outside until about the time of my previous CT scan. And this past month has been filled with walks. For yes/no habits (like medication adherence), Meetrics shows your current streak, your longest streak, and a Bayesian probability estimate of your true success rate. That last one sounds academic, but it's genuinely useful — it tells you whether the probabiliity of some relation along with its uncertainty. For example, below are the estimates of how Miralax (a laxative - I have colon cancer) affects my bowel movements (BM) the next day. It shows us the probability of me having more than 2 BM in the left image, and the probability of me having at least 1 BM in the right image. What's counter intuitive is that it seems that not having Miralax (miralax = 0) results in more bowel movements. But the reason for that is that diarrhea is a side-effect of one of the chemo's and when that starts I stop taking the miralax. The right image suggests that half a dose of miralax results in highest probability of at least 1 BM - I have no explanation for it being higher than miralax=1 other than there isn't enough data and you can see that in the heatmaps of the Bayesian estimates. This is the premium feature I'm most proud of. The Analyst tab connects to