You create each External Service based on a master iView. Read also
External Services and Master iViews.You should create an External Service for an iView that needs a lot of space in the Browser window and therefore occupies the entire page. For example you can create an External Service for an R/3 transaction. This External Service points to the related master iViews and takes on its properties.
Creating External Services Based on a Master iView Creating External Services for SAP Transactions Creating External Services for SAP MiniApps Creating External Services for SAP IACs Creating External Services for BEx Web Applications Creating External Services for the Crystal ReportCreating External Services for a Server Page Application