Sunstop: UV Index & Tan Timer

KNOW EXACTLY WHEN TO STOP.

Sunstop tells you how long skin like yours can stay in the sun today before burn risk rises. One number, computed from your skin type and the local UV forecast, shown in full, for free, every day. No account. No trial. Nothing blurred.

Most UV apps hide that number behind a paywall. It is the one thing everyone should see, so it is the first thing you see.

AN ESTIMATE, NOT MEDICAL ADVICE

Sunstop estimates burn risk from published dermatology (minimal erythemal dose by Fitzpatrick skin type) and the hourly UV index. It cannot see your skin, and UV damage builds up below the point of burning. When in doubt, stop earlier. Sunstop never promises a tan.

HOW IT WORKS

1. Allow location, or pick a city. Sunstop reads the local UV forecast.

2. Answer six questions to find your skin type, I to VI. Every type burns, including the darkest.

3. Read your number: today's burn ceiling, the UV window, and the minutes to your vitamin D target.

FREE, FOR EVERYONE

- Burn ceiling: the minutes before burn risk today, for your skin type and your goal.

- UV now and the hourly UV curve, with the peak marked.

- UV window: the hours when protection matters most.

- Vitamin D: the minutes to your daily target at today's peak.

- Cloud cover, temperature, sunrise and sunset.

- Saved places, so you can compare home with where you are going.

- Retake the skin quiz any time. Change your goal any time.

SUNSTOP PRO

- Guided sessions: Before, During and After, with timed rounds built from your ceiling. Sunscreen extends the time by roughly the square root of its SPF, never past 120 minutes, and reapply is always scheduled at 90 minutes.

- Flip alerts: turn over, reapply, cool off, done. They fire with the phone locked and face-down on the towel, and the countdown lives in an ongoing notification.

- Health Connect: every completed session writes your time in daylight to Health Connect.

- History and streaks: every session, every week, with no loss-aversion tricks.

HONEST PRICING

- Sunstop Pro is $29.99 per year, or $4.99 per month for a short season. There is no weekly plan.

- The UV index and your daily ceiling stay free whether or not you ever subscribe.

PERFECT FOR

- Fair skin that burns in twenty minutes and needs a real number, not a guess.

- Beach and pool days, hikes, gardening, sport: anywhere the sun is the plan.

- Anyone tracking vitamin D through the winter.

- Darker skin types who are told they do not burn. You do, later and less visibly.

Weather data from Google, with Open-Meteo as a fallback.

SUBSCRIPTION

Sunstop Pro is a yearly or monthly subscription that renews automatically until you cancel. Cancel any time in Google Play > Subscriptions: cancelling stops the next renewal and you keep Pro until the period you already paid for ends.

Terms of Service: https://aylan-apps.com/privacy/sunstop/terms-of-service

Privacy Policy: https://aylan-apps.com/privacy/sunstop/privacy-policy