Your Apple Watch collects amazing health data — but never tells you WHY. Correlate finds what actually affects your health using real statistics: 🔬 Granger Causality — detects if X causes Y (up to 14-day lag) 📊 Change Point Detection — finds when something shifted 🧬 Bio Age, Strain Score, Body Battery, Sleep Debt No hardware needed. All analysis on-device. Privacy-first. Free tier included. Built by a solo indie dev.