Inaccurate AM Sun
When I am outside in August for 2 hours beginning at sunrise, this early-morning window produces little to no meaningful vitamin D in the US zone 8 (34°N).
Yet, this tracker has me at 2000 IU.
Vitamin D synthesis requires UVB (roughly 290–315 nm). These short wavelengths are strongly absorbed and scattered when the sun is low because the path through the atmosphere (and ozone) is much longer. Practical thresholds for useful vitamin D production are generally solar elevations above ~35–45° (when your shadow is shorter than your height is a common rough guide, corresponding to ~45°). Below that, UVB is minimal or effectively absent for cutaneous vitamin D production even under clear skies.
Yet, this tracker has me at 2000 IU.
Vitamin D synthesis requires UVB (roughly 290–315 nm). These short wavelengths are strongly absorbed and scattered when the sun is low because the path through the atmosphere (and ozone) is much longer. Practical thresholds for useful vitamin D production are generally solar elevations above ~35–45° (when your shadow is shorter than your height is a common rough guide, corresponding to ~45°). Below that, UVB is minimal or effectively absent for cutaneous vitamin D production even under clear skies.
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改进
增加中文就好了哈哈哈
Love it!
Need Apple Watch version tho
Total Lifesaver
Avoid overusing toxic sunscreen with this app. Works very consistently. Most valuable free app on my phone.
Buggy
Constantly pauses itself when it should be running in the background
Very useful app
It is a very useful app that shows the uv index way more exactly than other apps - especially compared to the native weather app on iPhone. I would love an App for Apple Watch as well, because that would make tracking the uv exposure a lot more comfortable.
Chinese！
If possible we need Chinese thank you!
REQUEST: Add field to data
When Sun Day entries get pulled into the Foodnoms app from Apple Health it uses the ‘Source: Sun Day’ field from the structured data as the title. I think if you added ‘Food Type: Sunlight’ or something like that it would improve how this displays in other apps.
Best app for vitamin d
Tracks
1. how long you can be outside
2. Clothes you are wearing
3. Whether you’re wearing sunscreen or not
4. Skin tone
5. IU’s you getting
6. Etc
And then warns you if it’s not light enough out and you should take vitamin d
This is clearly the best app, I’ve seen other apps, this one is better and it’s free just get it.
1. how long you can be outside
2. Clothes you are wearing
3. Whether you’re wearing sunscreen or not
4. Skin tone
5. IU’s you getting
6. Etc
And then warns you if it’s not light enough out and you should take vitamin d
This is clearly the best app, I’ve seen other apps, this one is better and it’s free just get it.
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Amazing app
This app is very good, especially considering that it's free.
It has a beautiful adaptive design and is easy to use and configure. That's worth four stars!
There is one drawback: despite its excellent handling, I personally would like to see an overview of the recordings and mirroring to the Apple Watch for easier and faster start-up.
All in all, however, it is THE app for me to track my time in the sun.
It has a beautiful adaptive design and is easy to use and configure. That's worth four stars!
There is one drawback: despite its excellent handling, I personally would like to see an overview of the recordings and mirroring to the Apple Watch for easier and faster start-up.
All in all, however, it is THE app for me to track my time in the sun.
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Love it!
This latest version irons out all the niggles of the original: it now keeps a session if you accidentally close the app, and the UV index seems to tally to local weather app now. I love it, thanks Jack!
Good and simple
If apple watch can install this app , that’s could be better
A suggestion
There is data on sunshine hours in Apple Watch, which can be obtained directly by Health, and then clothing can be predicted by weather temperature, so that the daily data can be automatically recorded rather than recorded by hands
UI not friendy for iPhone mini series
i hardy to choose skin type in this UI
Super cool and useful
I love the app. Pretty useful to get sun exposure info and estimate our vitamin D. I use it in France.
The only feature I miss is an Apple Watch extension to be able to launch a sun session even when I don’t have my iPhone next to me.
The only feature I miss is an Apple Watch extension to be able to launch a sun session even when I don’t have my iPhone next to me.
Cool!!
Is possible help in translation in some way?
Track Your Vitamin D Intake
Great app. Simple and easy way to track your daily vitamin D intake.
Really smooth
We need more devs like you. Works great, no bugs. No info getting leaked.
Great Start!
This is great - like one other reviewer I’d definitely like to see something about sunscreen factored in. But also a live activity in iOS would be great cause man do I forgot I’m tracking and then next thing I know I’m getting a billion and 3 IUs according to the app when in reality I just forgot to stop tracking. Thanks Jack - love seeing little passion projects like this.
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Sun Salvation
Living on Earth may be expensive, but it includes an annual free trip around the Sun, and daily D.. vitamin D.
