The first step to create an app is to start with creating an app which contains the App Metadata information.
You create an app with the following command:
$ iectl publisher standalone-app create \
--appname "my cool app" \
--reponame "mycompany" \ # This relates to the repository name of the docker image.
--appdescription "my cool app" \
--iconpath "/path/to/my/icon" \
--webAddress "www.test.com" \ # Web address for application. [Optional]
--signUpType "SignUpWithoutCode" \ # signUpType: ["SignUpWithCodeOnly", "SignUpWithOrWithoutCode", "NoSignUp", "SignUpWithoutCode", "None"] [Optional]
--externalUrl "www.siemens.com" \ # This URL will be used by IEM app UI to open, application iframe embedded in IEM. [Optional]
The app is afterwards available within your local workspace as well as all generated metadata (i.e. the app ID).