Personal Bests vs Undercurrent

Personal Bests finds the fastest efforts hidden inside your workouts and awards you medals for them, with nobody to compete against but yourself. Your fastest 5K might be kilometers 7 to 12 of a half marathon. Your best mile might be buried in the middle of a long run. Personal Bests looks inside every workout in Apple Health, finds your fastest segment for every distance you care about, and ranks it against your whole history. Just You vs. You Personal Bests isn't a social network. There's no feed, no followers, no leaderboard of strangers and no challenges telling you to go faster. You earn gold, silver and bronze for real work, and the only person you're up against is you. Your Game, Your Rules • Choose the distances that count: 400 m, 5K, 10 miles, a marathon or anything else, for every sport. • Choose what you're compared against: all-time, the past year, or any window of days, weeks, months or years. • Coming back from an injury or a break? Rank against the last three months instead of your all-time best. • Keep the medals you've earned, even after you beat them, or let them move on. • Rank indoor and outdoor workouts separately, so a treadmill run isn't compared with a trail run. Find Your Fastest Efforts • Segments can start and end anywhere in a workout, not just at the start. • Running, cycling, swimming, rowing, paddling, walking, cross-country skiing and more. • Your whole Apple Health history, from Apple Watch, iPhone and other apps. • New workouts are analyzed automatically, even in the background. See Where You Were Fastest • On iPhone, your fastest segments are drawn on the route, each in its own color. • Leaderboards for your fastest times, longest workouts and farthest distances. • A short written summary of any workout, using Apple Intelligence where it's available. Keep Bad Data Off the Podium • Forgot to stop your watch on the train? Segments that are too fast to be true for you are flagged, judged against your own history. • Crop a workout to the part you actually did, or remove GPS spikes with one tap. • Your Health data is never changed. Celebrate Your Progress • Get a notification when a new workout earns a medal. • "While you were away": a recap of your new medals and training when you come back to the app. • Rankings and Recent Bests widgets for the Home Screen and Lock Screen. On iPhone, iPad & Mac • Your iPhone reads Apple Health and does the analysis. • iPad and Mac show your workouts, rankings and medals, with the list and details side by side. Private by Design • No account, no ads, no tracking. • Analysis runs on your device. • Syncs only through your own iCloud, and you can switch that off. • Read-only access to Apple Health. Make It Yours • Three app icons and three themes. Personal Bests is for anyone who loves earning medals but doesn't need to race strangers for them: runners tracking PRs from 400 m to the marathon, cyclists comparing their best 40K across seasons, swimmers, rowers, and everyone who has ever wondered, "When was I actually at my fastest?"

You know something is off, but what? Headaches that seem random. Energy that crashes for no reason. You suspect a pattern, but every time the doctor asks "have you noticed any patterns?" you draw a blank. Undercurrent is a private symptom log and food diary for the small things, and the patterns hiding inside them. Use it as a headache log, a food symptom diary, or a flare journal for a chronic illness. LOG IN FOUR TAPS OR FEWER Symptoms, food, medications, activities, and observations. Quick chips for what you log most. Voice if you'd rather. Or just tell the on-device AI assistant in plain language: "headache after lunch" and it handles the rest. WHAT WE'VE NOTICED Once you've logged enough events, the Insights page surfaces co-occurrences in your own data, phrased in soft language. None of it claims to cause anything. You decide if it's signal or noise. • Pre-window pattern: what tends to show up in the hours before symptoms • Time-of-day cluster: when symptoms tend to gather • Day-of-week peak: which days run hottest • Recurring sequence: a familiar arc, repeated • Co-occurrence: tags that appear alongside symptoms • Seasonality: a year, at a glance (Pro) • Environment: weather, barometric pressure, humidity, air quality, for migraine weather and pressure patterns (Pro) • Long-term cycles and intervention effectiveness (Pro) A REPORT YOU CAN HAND TO YOUR CLINICIAN One tap exports an editorial PDF: auto-numbered observations, frequency tables, time-of-day distributions, and an event log. Black-and-white printable, sized for a five-minute appointment. No portal login on the other end. READINGS: GLUCOSE, HEART RATE, BLOOD PRESSURE, WEIGHT Your numbers sit on the same timeline as everything you log. Log a reading by hand in a couple of taps, or import from Apple Health with Pro, including a CGM's glucose every five minutes. ON YOUR WRIST Log what you log most with one tap on Apple Watch. Set severity with the Digital Crown, mark a symptom improved later, or start from its watch face complication. MEDICINE CABINET AND PILL BOX Set a dose schedule once and the medications you take regularly log themselves. A daily pill box shows what's taken and what's still due. APPLE HEALTH INTEGRATION Pull in workouts, mindful sessions, and readings automatically (Pro). TRACK MULTIPLE PEOPLE (PRO) Separate threads for yourself, your kids, or anyone you care for. 100% PRIVATE BY DEFAULT • No account required, start logging immediately • All data stored locally on your device • AI runs on-device using Apple Intelligence; nothing is sent to a server to be analysed • Optional iCloud backup, protected by Apple's encryption • No analytics, no tracking, no ads BUILT ON PUBLISHED RESEARCH Across 85 clinical studies, self-monitoring was the most effective technique in digital health interventions for chronic conditions. FREE FOREVER • Unlimited logging, medicine cabinet, and manual readings • Today, Timeline, and Calendar views • AI chat assistant for plain-language logging • Basic Insights: pre-window, time-of-day, day-of-week, sequences, co-occurrences UNDERCURRENT PRO · ONE-TIME PURCHASE · $19.99 Pay once, keep everything forever. No subscription, no recurring charges. • Weather, pressure, and humidity correlations • Long-term cycles, seasonality, intervention effectiveness • Full clinician PDF report • Multiple people • Apple Health sync, including CGM glucose • iCloud backup Whether it's what shows up before your migraines or which foods leave you uncomfortable, Undercurrent gives you a quiet place to write it down. NOT A MEDICAL DEVICE Undercurrent describes statistical co-occurrences in your self-logged data. It is not intended to diagnose, treat, cure, or prevent any disease. Observations are informational only, not medical advice. Always consult a qualified healthcare professional about symptoms, medications, or treatment decisions. In an emergency, call your local emergency number. Notice what's quietly shaping how you feel.