"Get 15 minutes of sun" is useless advice.
At what latitude? Which month? What hour? With your skin? Change one and the real answer swings from 8 minutes to never, and for months of the year, in most of Europe, it genuinely is never.
- Your two dates
The moment you finish setup, VitaD gives you the two dates that shape your year: when your skin stops making vitamin D, and when it starts again. Calculated from the sun's real position over your city. Marseille and Lille do not share a winter.
- A timer that knows when to stop
Step outside, start a session. VitaD tracks what your skin is actually producing, weighted by skin type, age, and how much is uncovered. Past roughly a third of a sunburn dose your skin makes no more vitamin D at all, while the damage keeps stacking. VitaD stops you at that ceiling, never near a burn.
- Food in two taps
Tiles, not a food diary. Sardines, cod liver oil, eggs, fortified milk, in real portions from ANSES Ciqual data. Add your supplement once and it counts daily.
- One honest score
No invented blood level. You get a grade, A+ to E, over a rolling 30 days, measured against published recommendations. It rewards consistency and warns you above the safe limit.
- Nothing leaves your phone
No account, no server, no analytics. Everything stays on yourdevice, so we can't see it and there's nothing to leak. Wipe it all in one tap.
General guidance, not medical advice.
Know when the sun works for you.