HealthSync checks outdoor air quality and weather where you are, hour by hour, and tells you the safest window to be outside for your specific health condition. This page answers the questions we get asked most. If yours isn't here, email us — a real person reads it.
No. There is no sign-up and no login. Open the app, pick your conditions, and it works.
Exactly what it says. Air quality forecasts do not cover every variable in every location, and when too much of the data for your condition is missing, we would rather tell you we don't know than show you a confident number built on nothing. Try again later, or check a nearby city.
To look up the forecast for where you are. We ask for approximate location only — never precise GPS — because the air quality data is modelled on a grid about a kilometre wide. If you would rather not share it, tap "Enter a city instead"; the app works the same way.
iOS only asks once. To change it, go to Settings → HealthSync → Location, or use the "Open Settings" button the app shows you. You can also just type a city name.
Weather and air quality data comes from Open-Meteo. The thresholds we score against are published EPA standards for fine particles, ozone, nitrogen dioxide and the UV Index. Every one of them is listed on the app's Sources screen — including the handful we could not trace to a primary source, which we label as unverified rather than hide.
No, and the app says so. The Air Quality Index is official; our 0–100 reading is ours. It weighs the factors that matter for the conditions you selected and gives you one number for how rough an hour is likely to be for you specifically.
Because some days are bad all day. We show you the calmest stretch we can find, but if even that one crosses a threshold for you, we say so instead of implying it's a green light.
No. HealthSync is free, has no ads, no subscriptions and no in-app purchases.
Email nvsskalyan@gmail.com. Tell us your device, your iOS version and what you were doing when it went wrong, and we'll get back to you.
We collect nothing. The full policy is at our privacy policy page.