Know your UV number. Trust your safe window.
ChiRo turns ambient UV Index, your Fitzpatrick skin type, and today's SPF into one honest countdown — calculated entirely on your device, with nothing tracked, synced, or sent anywhere.
Four instruments, one control desk
Every feature exists to answer one question: how much longer is it safe to be outside, right now, for your specific skin.
Fitzpatrick Skin Matrix
Select your phototype, Type I through VI, using the standard dermatological scale to lock in your baseline solar tolerance.
SPF Exposure Multiplier
Enter your sunscreen's SPF — 15, 30, 50, or custom — and see the exact multiplier applied to your baseline safe-sun time.
Ambient UV Reference Log
Keep a manual, local register of UV readings for the places you frequent, so seasonal radiation shifts are easy to spot at a glance.
Tactical Countdown & Haptics
Start a fully local, battery-light countdown that gives a crisp vibration alert the instant your safe exposure limit is reached.
Your solar budget, calculated live
This mirrors the exact logic running inside the App — adjust the dials below and watch your safe exposure window respond.
Instrument-makers, not data collectors
We're a small team of instrument-makers at heart — people who like dials, timers, and numbers you can trust. ChiRo II: UV Index was built on a simple idea: sun safety shouldn't require a data plan, an account, or a stranger's server somewhere tracking where you tan.
Our mission is precision without intrusion. We wanted a tool that treats your skin like the variable it actually is — Fitzpatrick type, SPF strength, and today's UV reading — and does the arithmetic honestly, on your phone, with nothing phoned home.
ChiRo gives you a private data desk for solar exposure: punch in the local UV Index, pick your skin profile, set your sunscreen's SPF, and let a mechanical-feeling countdown timer do the watching for you, right down to a haptic buzz when your safe window closes.
Know your number. Trust your timer. Own your sun.
Nothing collected. Nothing to protect but your device.
1. Information We Collect +
We collect nothing. ChiRo has no sign-up screen, no account system, no email capture, and no location services. The values you manually enter — your Fitzpatrick skin type, the local UV Index reading, your chosen SPF rating, and your saved reference locations — are typed by you, for you, and never leave your phone.
2. How We Use Information +
Because nothing is transmitted to us, there is nothing for us to use, study, or monetize. Every calculation — your SPF exposure multiplier, your safe-sun countdown, your ambient UV log — is computed entirely on-device, in real time.
3. Data Storage +
All entries are stored locally in the App's private storage sandbox on your iOS device. There is no cloud sync, no remote backup service, and no server-side database associated with ChiRo.
4. Third-Party Services +
ChiRo contains no third-party analytics SDKs, no advertising networks, no crash-reporting trackers, and no embedded web content. The App makes no outbound network calls during normal use.
5. Data Security +
Because your information never travels off your device, the biggest security risk it faces is the same one your photos or notes face: physical access to your unlocked phone. Our minimal footprint keeps exposure low by design.
6. Children's Privacy +
ChiRo does not knowingly collect personal information from anyone, including children under 13, because it does not collect personal information from anyone at all. There are no chat features, social components, or data-collection mechanisms of any kind.
7. Your Control +
You are always in full control of your ChiRo data. There is no cloud backup to request deletion from and no account to close, because none exist. Deleting the App permanently removes every UV log, skin profile, and countdown history with it.
8. Changes to This Policy +
We may occasionally revise this Privacy Policy to reflect App updates or new features. Changes will be posted here with a new Effective Date. Continued use of ChiRo after an update constitutes acceptance of the revision.
9. Contact +
Questions about this policy can be sent to privacy@chiroiiuvindexapp.com.
👋 Talk to the team behind the dials
Got a question about your Fitzpatrick setting, found a bug in the countdown math, or just want to tell us how your beach day went? We'd genuinely love to hear it.
⏳ We read everything and typically reply within 24–48 hours.