A guided tour through Dart and Flutter.
Once you've set up your Flutter project, you can start building your cross-platform UI. Here are the steps: read cross-platform uis with flutter online free
Flutter stands out because it doesn't rely on a "bridge" to communicate with the host platform; it compiles directly to native ARM or Intel machine code, as well as JavaScript for the web. This ensures high performance across all screens. A guided tour through Dart and Flutter
If you're new to Flutter, here are some online resources to help you get started: read cross-platform uis with flutter online free