Twitter co-founder unveils new app 'Sun Day'
Jack Dorsey, best known for co-founding Twitter, just launched Sun Day—a new app that helps you figure out how long you can safely stay in the sun and keep your vitamin D levels in check.
The app takes into account things like your skin tone, what you're wearing, local UV index, and even cloud cover.
This launch follows closely on the heels of BitChat, his recent messaging app that lets people chat without internet using Bluetooth.
Sun Day and BitChat both use AI coding assistant Goose
Sun Day gives personalized sun exposure tips and uses science-backed models for vitamin D absorption. It's available on iOS and GitHub so more people can try it out.
Both Sun Day and BitChat were built with Goose—an AI coding assistant from Dorsey's company Block—which lets developers focus on making cool features instead of getting stuck in code details.
While BitChat has faced some questions about security, both apps show how Dorsey is blending AI with everyday tools to make tech more accessible.