Symbian Foundation Wiki
Artjom Vejsel kindly host a mirror of the Symbian Foundation Wiki. link
Symbian Foundation Mercurial Repository
Artjom Vejsel also host a copy of the mercurial repository that contains the source code of Symbian and is useful to follow the procedures mentionned in the Wiki. link
Symbian Open Source Archive
For one short year, Nokia open-sourced their Symbian smartphone operating system. This is an archive of most of the symbian.org website from December 2010. Included are MediaWiki dumps, Mercurial repository bundles, mailing list archives, and webforum crawls. link
Nokia Developer Wiki Archive
This is an archive of most of the http://developer.nokia.com/community/wiki/api.php website last updated on 01-07-2014. There are MediaWiki dump and files that were uploaded to wiki, including articles in doc/pdf, code samples and some optional APIs in zip. It could be downloaded here. Its content is listed on this page to make it more accessible by search engines.
Accessroot Arteam’s Symbian tools and tutorials
This is a collection of tools and tutorials created by the Accessroot Arteam. They are mostly focused on reverse engineering and implementation details of Symbian OS. Since their official website is frequently offline here is an archive of all their Symbian work (link) and of all of their work available on their website in 2016 (link).
N-Gage docs, firwmares, …
This is sort of the “ancestor” projet to this one (Symbian Archive). NGemu had the goal of being an N-Gage emulator. While the projet has now changed it’s approach and is now living somewhere else, a lot of the n-gage specific documentations, tools and articles that were collected haven’t yet been added to this website. link
This is a collection of patched tools and scripts for compiling them, for building symbian applications. It also contains patches for different S60 and UIQ SDKs, to enable building in unix-like environments. link