Last week, Facebook officially welcomed Instagram into its family as it passed the 5 billion photo milestone. In my coverage, I wrote: “It’s already on Android and iOS, so maybe a Windows Phone app is in order, although we haven’t heard anything of the sort.” Today, Tom Warren of The Verge points to the following video from Nokia, which purportedly shows an Instagram app for Windows Phone:

Did you miss the Instagram app? Yeah, I did too upon first viewing. In fact, I couldn’t spot the iconic logo at all, nor the “app running as a live tile with comment and like information from Instagram.” I thus got in touch with Warren, who told me it’s at the 50 second mark, although the app in question might be Vimeo.

Regardless of what the video shows, Warren’s sources say Instagram is coming to Microsoft’s Windows Phone operating system as a standalone app before the end of 2012. This is great news for both Microsoft and Windows Phone fans alike.

When the announcement that Facebook was buying Instagram first surfaced in April 2012, some believed that it was the end of the popular app. Facebook then insisted that it would be keeping it around, however, and sites like ZDNet speculated that maybe the extra resources would result in a Windows Phone app.

There are various Instagram-like apps for Windows Phone, such as Bubblegum, developed by two former Microsoft employees, and Instagram clones such like InstaCam, which are available in the Windows Phone Marketplace. Yet it’s not that easy.

If it was simply a question of copying Instagram, then Facebook wouldn’t have bothered acquiring the app. The problem is that people are already using Instagram and it’s difficult to get them to switch (much like for Facebook). As such, Microsoft has no choice but to convince developers to bring popular apps to its platform.

Some apps are easier than others. Microsoft was once a key investor in Facebook and has a close relationship with it. Microsoft owns Skype, which is integrated in Windows Phone 8. The real challenge is popular apps by developers that Microsoft doesn’t have good relationships with, and its execution in that area will either help or break Windows Phone.

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