WebClient UI serves as a framework for stateful applications in SAP S/4HANA for customer management 1709 and 1809, and SAP S/4HANA Service 1909.
The latest version delivered with release 1909 is implementation of SAP Fiori 3 guidelines.
WebClient UI apps can be accessed from Fiori Launchpad in standalone and FLP integrated mode.
Standalone mode is WEBCUIF classic. Applications are accessed from FLP tile and loaded within WEBCUIF shell (a.k.a L-Shape), in a separate window. Standalone is the only mode where Interaction Center scenario is available.
In FLP Integrated mode, the applications are hosted by Fiori Launchpad, a single entry point for all the apps available through catalogs and business roles. FLP integrated mode enables consistent user experience and seamless in-place navigation between WEBCUIF apps and other app types. It also makes use of Fiori Launchpad features such as navigation history, central search, Web Assistant and user settings.
WebClient UI in SAP S/4HANA supports Extensibility concept and cross-product themes.
For details on how to launch WEBCUIF apps from/within Fiori Launchpad, visit the following blog posts.