This app provides personalized recommendations for when to open your windows based on live weather, indoor readings, and HomeKit sensor data. It helps prevent mold, maintain a healthy indoor climate, and save energy by airing your home effectively.






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Köln is great, but it's not the only option. Explore 9+ similar apps for iPhone and iPad, each reviewed and rated by real users. Find free alternatives, premium upgrades, and hidden gems.






This app provides personalized recommendations for when to open your windows based on live weather, indoor readings, and HomeKit sensor data. It helps prevent mold, maintain a healthy indoor climate, and save energy by airing your home effectively.




Get hyper-local rain predictions for your exact GPS location. See live radar, a 2-hour nowcast, and a 24-hour outlook with no ads or tracking. Receive rain alerts and severe weather warnings for Germany and Europe.






A minimalist weather app and widget for iOS that visually represents forecasts using color and clarity. It offers an AI-assisted summary to highlight essential information and allows for personalization of displayed data and units. Enjoy core features for free, with an option to upgrade for more.