What operating system used in nokia mobile phones?

The collaborative support from the industry for the growing power of the Psion software base led to the historic formation in 1998 of Symbian, a joint venture between Psion and phone manufacturers Ericsson, Motorola, and Nokia. Over the next few years Symbian helped bring forth the explosion of mobile device innovation—with Symbian software at the base of more than 100 million phones by 2006.
In 2008, the next step of Symbian evolution took place, with Nokia purchasing all Symbian assets and starting the software down the path to open source. As the Symbian Foundation and all its members look to the future and the billions of forthcoming interconnected mobile devices, it will be innovative collaboration—working together —that will help make people more productive, more creative and more entertained than ever before.