After creating the application components , you must save the model in order to see the newly created components. Application will not became available until the model is saved.
Yes, you can delete the model. First if the model has been deployed to a data location. You will need to delete the data location and drop the tables. This is done in the management tab.
Once you delete the data location, you can then delete the model. Again you do this under management tab. Navigate to Model Administration > Right Click on the Model > Delete.
