Symbian Developer Library
The definitive latest release of the Symbian Developer Library (SDL) and the associated C++ examples is linked below. It is aimed at all developers working with Symbian OS to create new applications, new system level components, operating system ports, and other Symbian OS products. The SDL documents the APIs and technologies common to all phones based on that version of Symbian OS, and the tools and utilities needed by system extenders and product creators.
Symbian OS v9.4 documentation and example source code
The documentation and example code for Symbian OS v9.4 is available within the S60 5th Edition C++ Developer's Library v2.0 section of the Forum Nokia Library.
Previous versions of the SDL documentation
Previous versions of the Symbian Developer Library are no longer available.