Message that usually follows a AppRegistrationResponseMessage and is used to upload a data app to the app store. Payload contains data app. Note that the message must refer to the prior sent, corresponding AppResource instance. The IRI of the ids:appArtifactReference must must match the IRI of the artifact which is the value for the ids:instance property. The ids:instance is specific for each representation. Therefore, if someone wants to upload multiple representations for an app, he has to state them using multiple ids:instance properties inside the AppRepresentation (and therefore inside the AppResource). Otherwise no mapping between payload and app metadata can be achieved.