After BitChat, Twitter co-founder comes up with app to track UV exposure, Vitamin D

Last week, Jack Dorsey unveiled an innovative Bluetooth-based messenger app, BitChat.

Twitter co-founder has come up with another creative app, Sun Day, which can help users track their exposure to Ultraviolet (UV) rays and Vitamin D.

Dorsey shared the news on X (formerly Twitter) that the Sun Day app is now available for iPhone users on the Apple App Store. For testers, the beta version can be accessed on Apple's TestFlight platform.

Jack Dorsey is using a generative Artificial Intelligence (gen AI)-powered coding tool, Goose, to develop the app. The source code of the Sun Day Tracker app has been rolled out on GitHub for independent app developers to test run the application.

The Sun Day app can log a user's real-time UV exposure based on the location. It can even calculate Vitamin D based on UV. For this, the user has provided details such as skin type and also what clothes they are wearing on that particular day.

This will help the app to show how much the user was exposed to the UV and how much Vitamin D he/she gained on that particular.

Sun Day app UI.

The app also displays Moon phase at night, Sunrise/sunset times and as the personal information will be linked with the Apple Health feature on iPhone. This way is fully protected against leakage of personal data.

The Sun Day app comes in small and medium widgets for the home screen of the iPhone.

The Android version is yet to be developed. It is expected to be released in the coming weeks.

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