Privacy Policy

Air Quality Index: Haze MY SG · Last updated 15 September 2026

The short version

Haze has no accounts and no sign-in. We never ask for your name, email or phone number. Your location is rounded to about 1 km on your phone before it is sent anywhere, and your saved places stay on your phone.

Your location

If you allow it, Haze reads your approximate location to find the nearest air quality station. On Android the app only asks for approximate location. On both platforms the coordinates are rounded to two decimal places (about 1 km) on your phone. Only that rounded location is sent to our server.

Our server uses it to pick the nearest station and to fetch the 5-day forecast and the weather, then answers. It does not save your location. To get the forecast and weather, the server passes the rounded location to Open-Meteo, a weather data service.

Like any website, our hosting provider (Vercel) keeps short-lived request logs to run and debug the service. Those logs include your IP address and the rounded location in the request.

You can use Haze without location. Turn it off and pick a station as a saved place instead.

Saved places, settings and the widget

The places you save (a name you type and a location rounded to about 1 km) and your chosen voice and colours are stored on your phone. They are not sent to us. When you look at a saved place, only its rounded location is sent, the same way as above.

The home screen widgets keep a copy of the latest reading, forecast and weather and the rounded location on your phone, and ask our server for fresh ones about every 30 minutes. On iPhone, when Haze is set to “Where I am”, the widget also reads your approximate location, rounded to about 1 km the same way, so it follows you when you travel. It uses the location permission you already gave the app and asks for nothing more.

Where the air quality data comes from

Readings come from Malaysia’s Department of Environment (DOE) and Singapore’s National Environment Agency (NEA). The forecast comes from the Copernicus Atmosphere Monitoring Service (CAMS) through Open-Meteo. Our server fetches the public DOE and NEA data. Nothing about you is sent to DOE or NEA.

Analytics

We use PostHog, hosted in the EU, to learn which features get used and which regions the app is popular in. The app sends a small set of events, such as “app opened”, “reading shown”, “voice chosen”, “plan tapped” and “purchase completed”. They carry the Malaysian state (or “Singapore”), the air quality band, the voice and colours in use, which widget sizes are on your home screen, your phone’s platform and the app version.

If the app hits an error or crashes, PostHog also receives an error report: the error message, where in the app it happened and the app version, so we can fix it.

Events never include your coordinates, a station name or the names of your places. They use a random ID created when the app is installed, which is not linked to your name, email or store account. Analytics does not run in development builds.

Purchases

Haze Pro is sold through Apple’s App Store or Google Play, and managed by RevenueCat, our purchases provider. To check whether you have Pro, the app sends an anonymous ID generated on your phone. We never receive your payment details, and the ID is not linked to your name or store account.

What we do not do

Deleting your data

There is no account, so there is nothing for us to delete on request. Deleting the app removes your saved places, settings and the widget’s copy of the reading. Analytics events carry a random install ID rather than your name or email, so we have no way to look up one person’s events. Your purchase stays with your App Store or Google Play account and can be restored after reinstalling.

Children

Haze is for a general audience and is not directed at children under 13.

Changes

If the app starts handling data differently, this page changes first and the date at the top changes with it.

Contact

Twiddle Thumb Studio, Malaysia. hello@twiddlethumbstudio.com