The idea behind this application is that it will help you track and manage your Vitamin D. This new version integrates with the Apple Health app to make seamless data exchange possible in the following ways: * on setup, profile information is fetched from the Health App if the user allows it * the user's weight (a factor in D generation) is fetched on an ongoing basis, making it unnecessary to update it * the app will write vitamin D doses, including session information into the Health app You setup basic information one time, like your height and weight and skin type and then any time you are outside, during the prescribed hours (and parts of the year), you can have it compute the amount of D you are getting in a stopwatch interface. It will also track how long you can stay out and warn you when the time is up. The application will notify you with the next opportunity to generate vitamin D. Each day, you can see forecasts based on your location, and you can also see the solar position, your generated vitamin D vs. target etc. In the Pro version, you can see your exposures' history and you will be able to schedule future events for next exposures.