Custom enhancements and building new pages within the SAP delivered Web UI framework results in a highly flexible, integrated workplace - provided that you do not breach the SAP MVC architectural concept. Access on the same screen not only to CRM transactions, but also developed Web Dynpro exchanging data with third party tools, and feeding this data back into CRM or ECC transactions. The use of SAP LORD interface - usually, but not only, for Quotations and Sales orders.
Web UI, primarily developed for SAP CRM frontend, uses a typical three-tier concept associated with MVC architecture: presentation layer (user frontend, usually generated '.htm' view), business layer (process logic, technically BOL and GenIL), and persistency layer (database access, APIs - not necessarily CRM specific). This results in a very flexible, universal platform that can be used to access, process and integrate data from any system - SAP or non-SAP, www public data, any of your internal systems (using for example a web service communication).
