It's no secret that Skype for Windows Phone isn't quite the impressive app many expected to see brace the platform -- heck, people weren't expecting an app in the first place. While the app that debuted Sunday night in its final form is a good step in the right direction, oversights like the lack of push notifications for phone calls when the app is in the background and the missing support for low-end Tango hardware have raised some concerns about the quality commitment to the platform, especially because Microsoft now owns Skype.
So what the heck is going on? It's a valid question and one that may have been answered a few months ago with the initial release of the Skype for Windows Phone beta. The Verge did a report that publicized the app's lack of background support and Skype responded by saying the shortcomings were "not a Windows Phone platform limitation," but "a combination of how Skype works and how the Windows Phone OS works."
At the time that statement was rather vague, suggesting that Skype couldn't wrap its head around integrating its system in a method compatible with Windows Phone's push services. However it could be deeper than that, as Insideris has shared one tipster's insider info on the matter (who has learned this information secondhand):
Before putting full blame on Microsoft, remember that from the inside Skype is really a horrible piece of software terribly written and awful to the fullest. Its architecture and implementation is so horrible it makes programmers scream in the night. That’s why it is not updated evenly on all the platforms; some versions are older than others by a year or more. [...]
I have a friend-insider in MS, he says it took longer than they expected to port it to WP7 because damn thing was unstable, crashing all the time. The last bit I cannot prove of course, but that’s what I heard personally.
In this case the tipster's information is unverified and thus we can only treat this as a rumor. However, sources we have spoken to have also corroborated that Skype's internal architecture is indeed at odds with what Microsoft wants to accomplish with the service. Unfortunately that's all we know and it appears Microsoft will be hard at work to do some housekeeping inside of Skype.
Remember that the Windows Phone app is likely only a small part of Microsoft's strategy with the online calling service, because expectations are that Skype will be integrated into Windows 8 as well as the Xbox 360. Sounds like $8.5 billion might have netted Microsoft more trouble than it anticipated.
Source: The Verge