Instagram recently cracked down on third party Windows Phone apps like Instance, banning it from uploading to the official site. This could be all solved with an official Windows Phone version of Instagram which has yet to be launched. Vine is another app missing from the Windows Phone Store. If Windows Phone is going to ever challenge Android or iOS, it needs to make sure that the software everyone wants is available.
On the other hand, it could take a run-up to 200,000 apps and beyond to convince developers that it is financially worthwhile for them to develop a Windows Phone version of their apps. With momentum returning to the platform, perhaps it won't be terribly long before the Windows Phone Store hosts Instagram, Vine, and some of the other high profile apps it is missing.
Thanks, Anonymous Tipster!
source: Microsoft via NokiaPowerUser