Correlation Lab: Health Test

Stop guessing what helps. Start testing it. Correlation Lab turns your Apple Health data into small, focused experiments — one clear question at a time. Pick two things you're curious about (caffeine and sleep, steps and focus, meetings and readiness) and the Lab quietly tracks how they move together. No dashboards trying to show you everything at once — just a clear verdict, in plain English. WHY CORRELATION LAB Most health apps drown you in numbers. Correlation Lab asks one question well: "When X changes, does Y follow?" That's the kind of insight that actually changes what you do tomorrow morning. HOW IT WORKS • Pick two metrics — sleep, steps, resting heart rate, HRV, focus minutes, caffeine, readiness, meetings, and more • The Lab pulls what it needs from Apple Health, or you log it yourself in seconds • After about two weeks, you get an honest answer — stronger, weaker, or no real link — with a confidence level instead of false certainty • Every result comes with a "how this was calculated" breakdown and a correlation-isn't-causation reminder, always START FRESH, OR LOOK BACK Already have years of Health history? Use it for an instant first read. Making a change starting today — cutting afternoon coffee, adding an evening walk? Start a fresh, forward-looking experiment that only counts the days you actually live through, so you watch the relationship build in real time. PRIVATE BY DESIGN Your health data stays on your device. Summaries are written using on-device Apple Intelligence — nothing about your health is ever uploaded. Want deeper analysis? Optionally connect your own AI provider. Entirely your choice, entirely under your control. BUILT-IN TRUST • See exactly which days were included, excluded, or missing — and why • Spot likely confounders before you draw conclusions • Watch how a relationship shifts over time as you make changes • Export every experiment whenever you like — your data is always yours WHAT YOU CAN TEST Sleep vs. steps. Caffeine vs. sleep quality. Meetings vs. readiness. Hydration vs. energy. Protein vs. recovery. Blood pressure vs. rest. Body weight vs. activity. Or build any pairing you're curious about. CORRELATION LAB PRO Unlock unlimited experiments, every advanced Health metric (blood pressure, sleep phases, body composition and more), AI-written explanations, full lab history, and the ability to run several experiments side by side. Not a medical device. Correlation Lab surfaces patterns in your own data — it isn't medical advice or a diagnosis. Always talk to a healthcare professional about your health. Test one relationship in your life. See what you find. Privacy Policy: https://correlationlab.jozefowicz.dev/privacy Terms of Use: https://correlationlab.jozefowicz.dev/terms