Symbian OS is an operating system, designed for mobile devices, with associated libraries, user interface frameworks and reference implementations of common tools, produced by Symbian Ltd.. It is a descendant of Psion's EPOC.
Symbian is currently owned by Ericsson, Panasonic, Siemens AG, Nokia, and Sony Ericsson. Whilst BenQ has acquired the mobile phone subsidiary of Siemens AG the Siemens AG stake in Symbian does not automatically pass to BenQ - this will need the approval of the Symbian Supervisory Board.
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wikiSymbian Wbsite