Varzo vs Caffeine Half Life

Know your body. Optimize your recovery. Built for Apple Watch owners. Varzo turns the heart rate, HRV and sleep data your watch already collects into insights about your recovery, sleep, strain and energy — all processed privately on your device. An Apple Watch is required. Varzo reads the data your watch records; it does not replace it. ON YOUR WRIST, AND AT A GLANCE • Apple Watch app — Recovery, Strain and Body Battery on your wrist • Watch face complications in four styles, so your recovery is there every time you check the time • Home Screen and Lock Screen widgets on iPhone • Everything syncs from your iPhone automatically — nothing extra to set up AI-POWERED COACHING Personalized insights powered by Apple Intelligence. Get tailored coaching on your recovery, sleep, strain, and energy with all AI processing happening entirely on your device. On devices without Apple Intelligence, smart rule-based insights keep you informed. FOUR METRICS THAT MATTER • Recovery Score — Wake up knowing if your body is ready to push hard or needs rest. Calculated from your HRV, resting heart rate, and sleep quality. • Sleep Analysis — Go beyond hours slept. See your sleep stages, efficiency, and consistency to understand what truly restful sleep looks like for you. • Strain Score — Track your cardiovascular load throughout the day. Balance high-intensity training with proper recovery to maximize results. • Body Battery — Watch your energy level change in real-time. Start each day with a full charge and see how activity depletes and rest restores your reserves. SET GOALS THAT MOVE YOU FORWARD Create personalized weekly goals for workouts, steps, calories, hydration, and more. Track your progress with intuitive visualizations and stay motivated with daily insights. TRENDS & INSIGHTS View your 7, 30, and 90-day trends. Understand your personal baselines and see how your recovery, sleep, and strain evolve over time. PRIVACY FIRST — WE COLLECT NOTHING No analytics. No tracking. No accounts. No servers. Your recovery, sleep, heart rate and every other health metric are read from Apple Health, processed entirely on your iPhone, and never leave it — never uploaded, never stored in the cloud, never shared, never tied to an identity. AI coaching runs on-device using Apple Intelligence, so even your insights are generated privately. There is no sign-up, because there is nothing for us to store. SUBSCRIPTION TERMS Varzo offers an auto-renewable annual subscription with a 14-day free trial. Payment is charged to your Apple ID account when the free trial ends, unless you cancel at least 24 hours before it finishes. Subscriptions renew automatically each year unless auto-renew is turned off at least 24 hours before the end of the current period. You can manage or cancel your subscription in your App Store account settings. Terms of Use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://varzo.ai/privacy.html

Caffeine Half Life helps you estimate how caffeine leaves your system over time — so you can make more informed choices about sleep and energy. Highlights - Personalized elimination curve using your profile (e.g. smoking, pregnancy, oral contraceptives) when you choose to provide them - Sleep-readiness estimates based on your bedtime and caffeine threshold — approximate only - Apple Health: optional read/write for dietary caffeine, plus HRV correlation on the chart so you can spot patterns (you control permissions) - Widgets and Apple Watch complications for quick glances — including a trend graph complication - Interactive chart — drag to inspect caffeine levels and HRV at any time of day How it works The app uses a simplified pharmacokinetic model (Bateman equation) to estimate caffeine absorption and elimination based on your personalized half-life. Factors like age, BMI, activity level, smoking, pregnancy, and oral contraceptives adjust the half-life up or down from the ~5-hour population average. Important: This app is for general wellness and educational purposes. It is not medical advice and not a medical device. All estimates are approximate — individual metabolism varies. Consult a healthcare professional for health decisions. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/