ISS Detector vs UNISTELLAR App

ISS Detector helps users find visible International Space Station passes and predict satellite passes for their location. For each upcoming ISS pass, it gives the local start time, direction, highest altitude, and duration, and can notify users minutes before the pass begins. It checks the local forecast and indicates when clouds may prevent a sighting. Premium features add tracking for Starlink, Hubble, rocket bodies, planets, comets, and amateur radio satellites; amateur radio tracking includes transmitter information and Doppler shift calculations. Users can share sightings on social media. ISS Detector says it combines information from NASA, Heavens-Above, the Minor Planet Center, and yr.no weather. It is listed for Android, iOS, macOS, and web. The free plan includes ads and in-app purchases; ISS Detector Pro costs $17.99, paid once and includes all extensions with no ads. Its privacy policy says location calculations happen on-device and precise location is not stored on the maker’s servers. Google Play says data can’t be deleted.

UNISTELLAR App has no write-up on Specifiction yet; its figures are above.