Last updated: 11 November 2026
Revontulet does not collect or share personal data. The only exception is the optional aurora alerts: if you turn them on, a minimum of data is stored on the developer’s alert service so it can notify you. This policy explains what the app does with your location, what it sends over the network, and what alerts store.
If you allow location access, Revontulet uses your position to find your municipality and the nearest measurement station, and to work out whether it is dark where you are. This happens only on your device. Your location is never sent to the developer, to the Finnish Meteorological Institute (FMI) or to anyone else.
Aurora alerts use only a coarse area derived on your device (see below); your position itself is never sent.
The app uses location only while it is open. You can turn location access off at any time in Settings and choose a municipality by hand instead.
The app downloads magnetometer and cloud cover observations, and a cloud cover forecast, from FMI’s open data service (opendata.fmi.fi). Every observation request covers the same fixed area for all of Finland, and the forecast request asks for all ten alert areas at once, so no request contains anything about you or your location.
For the “soon” line and the outlook for tonight and tomorrow night, the app downloads solar wind data, the Kp forecast and geomagnetic storm watches from the NOAA Space Weather Prediction Center (services.swpc.noaa.gov) in the United States. These requests are fixed addresses, identical for every user, and carry nothing about you, your location or your area.
As with any internet request, FMI’s and NOAA’s servers see your IP address; their own privacy notices cover how they handle them.
If you turn on aurora alerts, the app also talks to the developer’s alert service (see below). The app and its widgets make no other network requests. The alert service itself does not use NOAA data.
The Home Screen and Lock Screen widgets show the same result as the app. They read the place you chose and the last result that the app stored on your device, in storage shared only between the app and its widgets on your iPhone. A widget has no location access of its own, never asks for location, and never sends your place anywhere.
When the stored result is old, a widget may download fresh data itself, using exactly the same FMI and NOAA requests as the app, described above. They are fixed requests that carry nothing about you.
Widgets collect nothing, send nothing to the developer or the alert service, and have no analytics.
Aurora alerts are off by default. Nothing is sent to the alert service until you turn them on in the app.
What is stored. When alerts are on, the alert service stores only:
Why. To send you a notification when the chance to see the aurora in your area reaches the level you chose. Nothing else is done with it.
What is not stored. No IP addresses, no position, no device or app details, no language and no name or account. The alert service keeps no request logs, and the web server in front of it keeps no access logs. Notifications are written in your language on your iPhone, so the service never needs to know it.
Where. On the developer’s own alert service, hosted by UpCloud in Helsinki, Finland. Notifications are delivered through Apple’s push notification service.
How long. The registration is deleted:
The alert service keeps one backup copy of its database, overwritten every night, so a deleted registration can remain in the backup for at most about one day.
How to delete it. Turn alerts off in the app. If you turn off notifications for Revontulet in iOS Settings, the app deletes the registration the next time you open it. If you delete the app, the registration is removed when Apple reports the address as invalid, or at the latest after 180 days.
The data is not shared with anyone.
Deleting the app removes all of these.
The app collects no data from anyone, including children, beyond the optional aurora alert registration described above, which contains nothing that identifies a person.
If this policy changes, the new version will be published at this address with a new date.
Questions about privacy: email support@revontuletapp.com or open an issue at github.com/juusimaa/revontulet/issues.