The Symbian Foundation has laid out a version release schedule, and a development timetable that calls for five iterations to be in production at a time.

The version of Symbian currently shipping requires a separate graphical layer, S60, but with "Symbian^2" those layers are combined in the first open-source version of the OS, which should be hardened for launch at the end of 2009.

By that point the Foundation reckons it'll have two more versions in progress, Symbian^3 and Symbian^4; the former taking submissions for features while the latter is at the core-development stage. Another year down the line Symbian^4 will be hardened and support for Symbian^2 will be coming to an end. The following diagram shows the progression:

The plan is nothing if not aggressive - even Apple doesn't try and launch two versions of its OS a year, and the chaps in Cupertino only have one set of hardware to support.

In the desktop world Apple has always enjoyed the advantage of only having to support a restricted set of hardware, those devices approved by Cuppertino, while Microsoft has been forced to support everything users could stick into a slot. The mobile-phone world might not be quite so fragmented, but Apple should still enjoy a distinct edge thanks to its locked-down hardware.

Having such frequent releases might enable Symbian to incorporate the latest fads and innovations, but it is a risky strategy depending on the level of compatibility the different releases can boast - which will in turn depend on the motivations of the Foundation members, and their commitment to the platform. ®

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