I've created a Delphi Win32 project that preprocesses Delphi.NET project files so that it can enable a project to be compilable for the Compact Framework (without errors), using the Delphi for .NET Compact Framework Technology Preview.
The source and binary for the Delphi Win32 project is available on CodeCentral.
In 2017, with the release of Delphi 10.2 Tokyo, Embarcadero introduced a specialized implementation of the Observer pattern into the System.Classes unit. While it has been in the wild for 9 years, it remains a "hidden" architecture for many, primarily because it serves as the invisible engine behind LiveBindings. Other than live bindings, you can also use the Observer pattern as a way to update component settings to the Windows registry, an .ini file, or persist it elsewhere.
System.Classes