Xamarin XAML Hot Reload allows us to make changes to our XAML without having to redeploy our app. When we have carried out changes to the XAML, we just save the file and it updates the page on the simulator/emulator or on a device. XAML Hot Reload is currently only supported by iOS and Android.
To enable XAML Hot Reload for Visual Studio on Windows, go to Visual Studio | Preferences | Tools for Xamarin | XAML Hot Reload.
To enable XAML Hot Reload for Visual Studio on Mac, go to Tools | Options | Xamarin | Hot Reload.
To use XAML Hot Reload, we have to use Xamarin.Forms 4.1+ with Visual Studio 2019 16.4+ (or Visual Studio for Mac 8.4+).