Symbian OS has been shipped in more than 330 million devices worldwide. Most of them are produced by Nokia. But for some years this platform didn’t get any essential changes and updates, while developers of Android and Windows Mobile update these operating system regularly integrating new functions and features. From today Symbian mobile platform becomes completely open source and available for free starting. Lee Williams, executive director of the Symbian Foundation noted that Symbian OS is dominant operating system for smartphone and now apps’ developers have much more opportunities. Now any organization or individual can download, use and modify Symbian OS code for any mobile device. It is expected that such decisive step will help Symbian operating system not only to stay dominant OS for mobile devices but also to improve its position.