The role of launch.json and tasks.json in VSCode

Launch.json describes the activity that takes place when the debugger is launched or the program is started.

It can rely upon a task defined in tasks.json - see "preLaunchTask".

You can reference variables defined in settings.json.

You can build up a dependency tree of tasks using "dependsOn".

If you want to launch an application such as an emulator as part of the debugger - and leave it running - then you define it as a background task. But it is necessary to set a problem watcher for it to work.

You will need to manually close the task in VSCode when you are done debugging.