Privacy Policy

Last updated: 12 September 2026

This describes what WeatherFairy ("the app") collects and what it does not. We do not describe anything the app does not actually do.

In short

• No account. We do not ask for your name, email, or phone number
• No precise location. Approximate location only
• No tracking. Location is read only when fetching weather
• No location stored on our server. Coordinates are folded into a 5 km grid

1. What we collect

Approximate location

What	Your device's approximate latitude and longitude, via Android's ACCESS_COARSE_LOCATION permission
How	We use the last known location from cell towers or Wi-Fi, and request a fresh one only if none exists. We never request continuous updates
Why	To show the weather where you are
Where it is kept	On your device only. The last coordinate is saved in app storage so the next lookup is fast
If you decline	Seoul's weather is shown instead. The app still works

What is sent when fetching weather

Fetching a forecast requires sending coordinates to our server. However, the server folds them into the national forecast grid (about 5 km) before storing anything. What gets cached is grid cell + forecast publication time, shared by everyone in that cell.

Our server does not retain who was where.

Diagnostics

We use Google Firebase Analytics to collect:

• What happened in the app — whether the lock screen appeared, whether setup completed, whether the app was killed in the background
• Device information — manufacturer, Android version
• What Google collects automatically — app instance identifier, approximate country, timestamps

These records contain no name, email, phone number, or precise location. We have an automated check in our codebase that rejects any event field that could identify a person.

There is one reason we collect this: lock screen apps are routinely killed by manufacturer battery optimisation, silently. We cannot fix what we cannot see.

2. What we do not collect

• Name, email, phone number, date of birth
• Contacts, photos, call logs, messages
• Precise (GPS) location or movement history
• Your usage of other apps

3. Advertising

The current version contains no advertising.

If we add advertising later we intend to use Google AdMob, which collects an Advertising ID. We will update this page and notify you inside the app before that happens.

4. Third parties

Google Firebase Analytics	Diagnostics · policy
Korea Meteorological Administration	Forecasts · queried by grid cell only
Open-Meteo	Forecasts (secondary) · queried by coordinates only
Amazon Web Services	Server and cache hosting (Seoul region)

5. Retention

• On-device location and weather cache — removed when you uninstall the app
• Server weather cache — replaced when a new forecast is published. Contains no personal data
• Firebase records — retained per Google's default retention period

6. Your choices

• Revoke location. Android Settings → Apps → WeatherFairy → Permissions
• Uninstall. Everything stored on your device goes with it
• Request deletion. Contact us and we will handle it

7. Children

This app is not directed at children, and we do not collect information that would tell us whether a user is a child.

8. Contact

See the support page.

9. Changes

If this policy changes we update the date above. Changes that add to what we collect will also be announced inside the app.