Polarglow tells you whether you can see the aurora tonight where you are, and wakes you up for it. It has no account and no sign-in. This page says exactly what the app and its server handle, and why.
Polarglow asks for your location while you use the app. Your precise location never leaves your iPhone for our server. The app turns it into a rough area, a one-degree cell (about 100 km across), and only that cell is sent to our server, so it can watch the sky over your area.
To show a place name, the app asks Apple's geocoding service on your iPhone, which Apple handles under its own privacy policy.
For each installation of the app, our server keeps:
It keeps nothing else: no name, no email address, no precise location, no contacts, no photos.
Our server's logs record each request's path, which includes the random installation id; each registration and each storm-night demo request, with the app's version and device software as the app reports them; and each alert sent, with the installation and place ids. They hold no IP addresses; to limit abuse, the server keeps addresses in memory, forgets each one 10 minutes after its last request, and never writes them down. The logs are kept for up to 30 days.
We delete an installation's data when Apple tells us its notification tokens are no longer valid (for example after you delete the app), or after 90 days in which the app has not contacted us. A subscription record that no installation uses is deleted 90 days after it expired. You can also delete it at any time in the app under Settings > Delete my data.
Subscriptions are sold by Apple. We use RevenueCat to check whether you are subscribed. RevenueCat receives an anonymous id made by its own SDK and your purchase records from Apple, under its own privacy policy. We never see your payment details.
The aurora forecast comes from NOAA's public Space Weather Prediction Center data. Cloud cover comes from Apple Weather: the app asks it for your area, and our server asks it for the cells it watches.
To understand whether the app works, we count a few events (the app was set up, the subscription screen was shown, a purchase was made, and where you found the app) and collect crash reports, through Google Firebase Analytics and Crashlytics. These carry a random app instance id and technical device information, and no location beyond the country Firebase infers. You can turn this off in Settings > Share analytics.
Polarglow is not directed at children under 13.
We post changes here with their date. Questions: support@flyingwhale.app.
Last updated: 2026-09-26.