WebBroker is good for really simple HTTP server functionality, but the more complex the system you want to build, the more you look into complete Delphi multi-tier frameworks such as DataSnap or RAD Server. They provide a lot more higher-level functionality than you can find in WebBroker.
The DataSnap framework has been part of Delphi since its early days and has been evolved over time. Delphi 3 introduced MIDAS technology to make it easy to build client/server database applications. In Delphi 6, this technology has been renamed to DataSnap and in Delphi 2009 it has been completely rewritten. In this new architecture, remote methods published by a DataSnap server look like database stored procedures that a typical SQL relational database system exposes. The dbExpress database access framework has been reused and a special DBX driver has been built...