I built this app following the MVVM pattern. I had an API service that was responsible for fetching the asteroids. For this service, I used URLSession and modern swift concurrency, using things like async await and group tasks. The API service fetched the JSON objects and returned it the viewmodel, which perfomred the buisness logic and provided the view the data for the user interface.

Users can change their unit preference in the unit control center. This was handled by storing an observerable object in the environment and passing this a bindable to the control center, so that one source of truth is maintained. Users unit selection are also stored in UserDefaults.