BigDose
Vitamin D sun tracker + safety
Free · Designed for iPad. Not verified for macOS.
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.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Sun Session goal editing — without stopping
Change your IU goal during an active sun session with a new live slider
Tap Goal in the session info row or the % / IU summary under the dial
The progress ring, time remaining and Live Activity update as you adjust
Quick preset chips for 600, 1000, 2000, 4000 and 5000 IU
If your goal goes past burn guidance, BigDose shows a caution — MED (burn risk) still tracks separately and only you stop the session
Fixed an issue where the goal editor sheet might not open during a session
Have a blast and please, keep bug reports coming!
Gp.
The developer, Grant Perry, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Grant Perry
- Size
- 10.4 MB
- Category
- Health & Fitness
- Compatibility
Requires iOS 26.0 or later.
- iPhone
Requires iOS 26.0 or later. - iPad
Requires iPadOS 26.0 or later. - Mac
Requires macOS 26.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 26.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- Copyright © 2026, Cre8vPlanet Studios, LLC. All rights reserved.
