BigDose

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.