Twitter co-founder and Square CEO Jack Dorsey has embraced vibe-coding, which has seen him release multiple new apps in just seven days. His second release in the last week is an iPhone app designed to help you track your UV exposure and Vitamin D levels.
The new app is called Sun Day, and it’s is available for iPhone in beta through TestFlight. There’s no clear sign of when it’ll be ready for a full release, or whether the app will come to Android.
Sun Day is a relatively simple app where you press a button to say you’ve walked into sunlight to begin to track UV exposure. You’ll then press it again to end the session, and it’ll give you an estimate of how much Vitamin D you’ve gained in that period.
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It uses your location’s UV index, cloud cover, and elements like sunrise or sunset times to calculate the amount absorbed. This app isn’t monitoring your actual phone’s intake of UV, so it won’t matter if the device is in your pocket. To get an accurate result, you’ll need to ensure you press the button every time you enter sunlight.
Sun Day also allows you to specify your skin type with six different options, plus you can pick what outfit you’re wearing to give it an idea of how much of your skin is visible. The app will also tell you when you may burn, according to these factors, giving you an idea of when to seek some shade.
Last week, Dorsey introduced a Bluetooth messaging app called Bitchat to help users communicate away from traditional connectivity like cellular or Wi-Fi. Bitchat’s notes say, “By leveraging Bluetooth Low Energy mesh networking, Bitchat enables direct peer-to-peer messaging within physical proximity, with automatic message relay extending the effective range beyond direct Bluetooth connections.”
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Soon after launch, Dorsey updated Bitchat’s GitHub page to say the app isn’t secure enough for some messaging. After criticism from various security experts, the page now reads, “This software has not received external security review and may contain vulnerabilities and does not necessarily meet its stated security goals. Do not use it for production use, and do not rely on its security whatsoever until it has been reviewed.”
Dorsey is on a run of releasing apps thanks to an AI open-source platform called Goose, designed to help users quickly turn ideas into functioning apps. Dorsey referred to Sun Day as a “weekend project,” so we may continue to see new apps from him in the near future.
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About James Peckham
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