When Nokia bought Symbian in 2008, nobody had any reason to believe their thoughts were anywhere near Open Source. Parts of the Symbian platform have been Open Source for quite some time and other portions have slowly been released.
Symbian, maker of the the world’s most popular mobile operating system, has just completed the transition to a completely open platform months ahead of schedule. While the kernel was opened up last year, the entire platform is now open source, primarily under the Eclipse Public License. By putting Symbian fully in the public domain, the Symbian Foundation is pitting it against Google’s Android.