I migrated my "ant" codename one project to maven using the app converter provided by CodeNameOne. I want to use only maven command lines to debug. Please, Could you write out the maven's command to do that?
In the IDO you can just press the debug button. It will launch the simulator in debug mode. There's no special command to run. If you do that from the command line you would need to initiate remote debugging which can work but you'll eventually need JDB or an IDE to connect to the app.
See How to remote debug java application from maven command line