PeakD4Y vs Heart Sit

SUBST4NCE is an educational harm reduction reference app providing research-backed pharmacokinetic data and drug interaction warnings. IMPORTANT DISCLAIMER This app is NOT a medical device and does NOT provide medical advice. It is a visualization and reference tool for educational purposes only. Always consult healthcare professionals for medical decisions. WHAT'S INSIDE Comprehensive Substance Database • 80+ substances across multiple categories • Published pharmacokinetic data (half-lives, metabolism pathways) • Mechanism of action explanations • Data quality indicators showing research confidence levels Interaction Checker • Check combinations of multiple substances • Understand potential interaction mechanisms • Color-coded risk levels based on published research • Plain-language explanations of why interactions matter Visual Timeline • See pharmacokinetic curves for substances • Understand onset, peak, and duration patterns • Multi-substance overlay visualization • Body load indicators Personal Context (Optional) • Add your biological factors for educational context • Weight, metabolism, and health considerations • Tolerance tracking • Current medications reference Research Citations • Every data point linked to published sources • PubMed IDs and DOIs for verification • FDA and WHO reference data • "Limited data" warnings for research chemicals CATEGORIES COVERED • Alcohol & Cannabinoids • Stimulants & Depressants • Psychedelics & Dissociatives • Prescription medications • Research chemicals (with appropriate warnings) • And more... SAFETY FEATURES • Emergency resources always accessible • SAMHSA helpline integration • Non-judgmental, educational framing • Privacy-first: all data stored locally on your device DESIGNED FOR • Harm reduction education • Healthcare students and professionals • Researchers and educators • Anyone seeking evidence-based substance information This app does NOT: • Provide dosing recommendations • Calculate "safe" times to drive • Facilitate procurement • Replace professional medical advice All information is compiled from peer-reviewed research and official sources. Users accept full responsibility for how they use this educational reference. 18+ only. By using this app, you acknowledge the terms and conditions presented at first launch. Questions or feedback? Contact us through the support link.

Did it actually work? The question every meditator secretly asks. Heart Sit answers it. Live heart rate from your AirPods Pro 3 or Apple Watch — captured every second, plotted around your timer, analyzed across weeks. Stop guessing. Start observing. LIVE HEART RATE Choose your sensor: AirPods Pro 3 (in-ear optical), Apple Watch, or Auto. Heart Sit shows which device is providing the reading in real time. No chest strap. No additional hardware. THE OBSERVED INSIGHT Every session ends with a one-line answer: "Your heart rate dropped 8 BPM." Or "Heart rate stayed steady — calm baseline." Compare this week to your 90-day baseline in Trends. Watch the line move. THE SETTLE SCORE Proprietary metric that measures how long it took your heart rate to reach its session minimum. Lower means you settled faster. Track it across weeks. Brag about it. APPLE WATCH AS REMOTE Open Heart Sit on your Watch — it becomes a control surface. Pause, resume, stop from your wrist. The Watch app stays alive for the full session via Extended Runtime Sessions. Your phone can sit screen-down across the room. PRACTICE TYPES Open, Zazen, Vipassana, Breath Focus. Each comes with appropriate defaults. Tag your sessions and see which practice settles you fastest. CONTEXT TAGS + MOOD Tag morning, evening, post-workout, stressed, calm. Capture your mood after each session. Heart Sit will show you which contexts produce your best practice. OVERTIME MODE The bell rings when your timer ends — but you don't have to stop. Continue as long as you want. Heart Sit counts the extra time and saves your full duration. EVERY DETAIL • Real-time BPM display + radial heart rate wave that shifts blue when calm, red when active • Optional haptic heartbeat — feel your pulse with every beat • Set an intention before sitting; recall it after • Session history with full per-second heart rate charts • Heart Rate Variability (HRV) reading per session • CSV export for power users • Beautiful share card — poster of your session • HealthKit integration: every session saved as a Mind & Body workout • Pure black, Georgia serif. No clutter. No animations to distract you. PRIVACY No accounts. No cloud. No analytics. No tracking. The app makes zero network requests. Everything stays on your device. NO SUBSCRIPTION. EVER. This isn't a wellness app trying to monetize your meditation. It's a measurement instrument for people who already have a practice. Download once. Use forever. REQUIREMENTS • AirPods Pro 3 (or AirPods Pro 2 with USB-C and HR-capable firmware) for live heart rate via earbuds • Apple Watch for live heart rate via wrist (any HR-capable model) • iPhone running iOS 18.0 or later Without either AirPods or Watch, Heart Sit works as a beautiful meditation timer with the same overtime mode and session journaling. For serious meditators who want evidence, not affirmation.