Sundog vs BigDose

Most people either avoid the sun entirely or stay out too long. Sundog helps you do neither. Built around four science-backed goals, Sundog gives you a personalized daily sun schedule — calibrated to your skin type, the live UV index, and real-time cloud cover. A smart timer tells you exactly how long to be outside, and your burn limit is always visible so you know when to head back in. Four Goals. One Routine. - Circadian Reset — Morning light sets your body clock for the day. A short session before 9am resets your sleep-wake rhythm, lifts mood, and sharpens focus. - Vitamin D — Midday UVB is your window. Sundog times your session to maximize D synthesis and stops automatically before you reach your burn limit. - Gradual Tan — Afternoon light has lower UV intensity. Sundog schedules your exposure when the risk is lowest and the result is real. - Sleep Optimization — Evening golden-hour light cues melatonin production, making it easier to fall asleep and stay asleep. Smart, Not Just Simple Sundog's timer isn't a countdown — it's a calibrated recommendation. It reads the live UV index and adjusts your session length automatically. Heavy cloud cover? Session extended. UV extreme? Pulled back. Your burn limit is always front and center. Built Around Your Skin Set your Fitzpatrick skin type once. Sundog uses it to calculate your personal burn limit at any UV level and adjust every session recommendation accordingly. Skin type I gets very different guidance from skin type V. Time-Window Gating Each goal has a scientifically appropriate time window. Circadian Reset is a morning-only session. Vitamin D is gated to the midday UVB window. Sleep Optimization surfaces in the evening. You always know whether your window is open, closing soon, or already passed for the day. Sun Tracker A visual emoji-based tracker shows your progress across the day — which sessions you've completed, which are still open, and what's coming up next. Daily Sun Insights Every day, Sundog surfaces a new insight — practical, evidence-based tips on UV, circadian biology, and getting more from your time outside. Available in English and Spanish. Sundog is designed for general wellness purposes only. It is not a medical device and does not provide medical advice. Consult a qualified healthcare professional before changing your sun exposure habits, particularly if you have a skin condition, a history of skin cancer, or are taking photosensitizing medications. UV exposure carries inherent risks. Always use appropriate sun protection.

Most sun apps pick a lane: vitamin D or sun safety. BigDose tracks both — in real time — so you can get outside with a plan instead of a guess. DOSE YOUR D. DEFEND YOUR SKIN. BigDose is built for people who want vitamin D from the sun and still respect their skin. We combine live Apple Weather, your skin type, sunscreen habits and sun angle to show when conditions are right for UVB — and when burn risk is climbing. YOUR DAILY COMMAND CENTER • Vitamin D window today — a sun-path diagram with Apple Weather sunrise and sunset, your personal D window, total daylight and how today compares to yesterday • Live UV, humidity, cloud cover, hourly and 3-day forecast from WeatherKit at your GPS • Daily sun IU goal with progress from sessions, supplements and food logged separately — no double-counting • Sun risk today when live sessions push past your personal burn threshold • Recommended daily IU tuned to age, skin type and goals LIVE SUN SESSIONS THAT RESPECT BOTH GOALS Start a session when your window is open. BigDose tracks elapsed time, estimated vitamin D toward your daily target and MED (burn risk) used on a live dial. Alerts when session safety is on: • Turn-over near 50% — rotate exposure • Optional Nanny Mode adds wrap-up at 75%, guidance at 95% and a 98% reminder • Stop-now at 100% MED — always, Nanny on or off You always end the session. We never do it for you. DOSE DNA — YOUR PROFILE, YOUR MATH Set Fitzpatrick skin type, typical coverage, sunscreen use, supplement defaults and a blood-level goal in ng/mL. BigDose personalizes session timing, safe max duration and safety alerts to you — not a generic chart. PLAN BEFORE YOU STEP OUTSIDE Session planner shows safe max duration at today’s UV, time to reach your D goal and milestone timeline. First-session guide walks new users through the dial, alerts and how to stop on their terms. PROGRESS THAT CONNECTS INTAKE TO LEVEL Log supplements and vitamin D food sources. Import labs when you have them. Progress estimates how your 25(OH)D trend is moving toward your goal using sun, pills and diet — with honest limits: modeled estimates, not a lab result. History keeps a ledger of sun, supplements and food by day. NOTIFICATIONS THAT MATCH YOUR STYLE Solar event reminders, next D opportunity nudges, optional AM light window alerts and session safety notifications when the app is in the background. Toggle what you want during onboarding or anytime in Settings. Nanny defaults on — turn it off when you want a lighter touch. SMART GUIDANCE, NOT A LECTURE Science tab explains how BigDose thinks about D and burn risk in plain language. Info buttons throughout — tap the (i) when you want context, skip them when you do not. BUILT FOR REAL OUTDOOR DAYS Live Activities keep an active session on your Lock Screen. Home Screen widgets surface today’s plan. Optional Apple Health import. High-contrast UI designed for glare, gloves and one-handed use outside. WHAT BIGDOSE IS — AND IS NOT BigDose is wellness guidance you choose to use. It is not medical advice, not a diagnosis and not a substitute for your clinician. Blood tests remain the source of truth for vitamin D status. Use shade, clothing and sunscreen beyond what any app can model. Whether you are optimizing morning light, chasing a short mid-day window or logging a supplement on a rainy day, BigDose helps you dose your D and defend your skin — same app, same dashboard, no false tradeoff. We ship often and read every report. Thanks for helping us make BigDose sharper every build.