Your Personal Vitamin D Coach
Dru transforms your smartwatch into an intelligent vitamin D tracker. Monitor real-time UV exposure, calculate optimal sun time based on your unique skin tone and location, and watch a vibrant dragonfruit fill up as you reach your daily sweet spot—protecting you from deficiency and damage.
You glance at your wrist during lunch and see a glowing dragonfruit on your watch face—3/4 filled with pink and speckled with black seeds. A gentle pulse indicates "perfect!" You just hit your daily vitamin D sweet spot. No more guessing, no more burning, no more supplements you don't need.