Depending on your development phase, the framework compiles your code in different ways or modes, which we called a build mode. Flutter's tooling allows the application to be compiled in three modes. Depending on our stage of development, we may choose between these compilation modes.    

• Debug Mode: This mode enables debugging of apps on a PHYSICAL device, emulator, or simulator. Assertions and service extensions are enabled here. Quick DEPLOYMENT is then achieved by optimizing compilation. 
• Profile Mode: In this mode, some debugging abilities are maintained, enough to analyze the app's performance while testing.  Tracing and some extensions are enabled in this case. On emulators and simulators, profile mode is disabled since their behavior does not reproduce real-world performance. The following command can be used to compile the profile mode: flutter run --profile 
• Release Mode: When deploying the app, this mode is used to minimize the SIZE of the footprint and maximize optimization. Debugging, assertions and service extensions are disabled here. Faster startup, faster execution, and less size are its key FEATURES. The following command can be used to compile the release mode: flutter run --release