Flutter offers a fast development cycle with hot reload, the ability to reload the code of a live running app without restarting or losing app state. Simply make a change to your source code, tell your IDE or command-line tool that you want to hot reload, and see the change in your simulator, emulator, or device.
To test this change some String Slightly and the Save it and you will be able to immediately see below messages in the Output window and App in the mobile is updated.
Initializing hot reload... Reloaded 1 of 391 libraries in 3,638ms.##FlutterCentralAds## This certainly removes the dependency to rerun the project every time you make changes.