Aurora Notifier, developed by Naturfakta AS, is a free Android app that helps users stay informed about the possibility of spotting the northern lights (aurora borealis / australis). The app utilizes Firebase Cloud Messaging to send notifications about the probability of aurora sightings, Kp-index (Hp30), solar wind parameters (Bz/Bt), and Kp-level forecast for the evening.

One of the unique features of the Aurora Notifier app is that it allows users to be alerted when other app users nearby have seen the aurora light display. This feature works by enabling users to upload aurora reports when they have successfully spotted the aurora light display themselves. The app also offers configurable notifications for local aurora probability, making it easier for users to plan and prepare for aurora hunting.

The premium version of the app, which can be purchased within the app, offers more technical information such as graphs of Kp-index predictions, cloud cover, and solar wind parameters. Additionally, the premium version offers some hidden features. Overall, Aurora Notifier is a useful app for anyone who wants to stay updated about the northern lights and increase their chances of spotting them.