The app showing an error saying an API key is needed is somewhat of a bug. The reason we currently don’t expose the weather data is because an API key is needed to poll the OpenWeatherMaps service and currently we are providing that key. The app is written in Javascript and thus cannot protect this key so we would need to build out some sort of API to proxy this data. We don’t have such an API at this point so thus that error message shows.
In the meantime, I will improve that message so at least it’s more informative and long term well see if we can open up some sort of API to get the same data our weather API is using.