Sources close to the Windows Live and Bing divisions at Microsoft have confirmed to BlogoFlux that Microsoft is currently developing both Bing and Windows Live Messenger iPhone applications.

Both applications are likely to be released alongside the upcoming Windows Live Wave 4 updates due in approximately March 2010. BlogoFlux understands that Windows Live is working aggressively to move its applications onto the iPhone. Last week Microsoft principal group program manager David Raissipour confirmed to Cnet news that “We are actively working on it” when questioned over the Bing iPhone plans.

Internally the philosophy “if you can’t beat them join them” is being adopted for iPhone development. Microsoft understands it needs to compete multi-platform for its web and cloud based applications if it wants to maintain and grow market share. Both applications have been available for nearly a year.

Stay tuned for more information on Microsoft’s Windows Live Wave 4 plans including what Windows Live Messenger will look like, tabbed messenger conversations and the Ribbon interface for Windows Live Writer exclusively here later this week.