Earlier this year, I bought a Nokia (NOK 2.03%) Lumia 920, after using two generations of Google (GOOGL -1.23%) Android phones. My initial impression was the same as most people who purchased it and Microsoft (MSFT -1.27%) Windows Phones -- a nice exterior design, cool hardware and software color schemes, and a unique operating system that was snappy and responsive. Unfortunately, the phone suffered from one fatal flaw -- its app store lacked many heavy hitters, namely Instagram.

Nokia's Lumia 920. Source: Techthirsty.com.

Instead of Google Maps, Nokia users must use Here Maps, or resort to using third-party apps such as GMaps, which attach a clumsy Google Maps overlay. Windows Phone users don't have an official YouTube app, since Google blocked Microsoft from creating one. Popular apps such as Angry Birds, which are free or ad-supported on iOS and Android, must be purchased on a Windows Phone. Windows Phone users also get last-generation, hand-me-down games, such as Temple Run and Draw Something, while iOS and Android users are already playing their sequels.

Even Facebook's (META -4.13%) app woefully trails its iOS and Android counterparts -- a recent update finally added multiple photo uploads, although it still lacks the ability to insert stickers and images into chat messages. Other apps and games that iOS and Android users use daily are simply non-existent on a Windows Phone.

Why Instagram for Windows Phone is no big deal
One frequently cited example is Instagram -- the popular photo-sharing app that was launched for Apple iOS in 2011 and Android in 2012. The app was purchased by Facebook in 2012 for $1 billion.

On Oct. 22, Instagram CEO Kevin Systrom finally announced that an official app would be coming to Windows Phone in the next few weeks.

Although the media made a huge deal about Systrom's announcement, it really doesn't mean much for Windows Phone users. Instead of waiting around like a neglected child for some attention from major developers, Windows Phone developers have already created unofficial, third-party versions of their favorite apps.

Are third-party apps superior to first-party ones?
The results have been surprising -- their unofficial apps are sometimes superior to the official ones in functionality and creativity. Since Windows Phone users have been asking for an Instagram app for over a year now, third-party versions of Instagram, such as Daniel Gray's Instance and Rudy Hyun's 6tag, have risen in popularity.

6tag, which is nearly indistinguishable from the official app on iOS and Android, allows filtered photo and video uploads, and also adds blur and collage tools -- features not found in the official app. Both Instance and 6tag are also updated more frequently than the official Instagram apps.

Rudy Hyun's 6tag. Source: screenshots from author's phone.

At first, Instagram didn't play nice with these third-party developers. Earlier this year, it changed its APIs (the access keys to its site), reportedly to "to fight spam to help prevent future attacks and increase security." This update rendered third-party Windows Phone Instagram apps useless, and prompted a backlash that resulted in Instagram reworking its APIs to allow Instance and 6tag back through.

In addition to 6tag, Rudy Hyun also created 6sec, a third-party app for Vine, which is considered another hole in the Windows Phone ecosystem. Vine is Twitter's popular micro-video sharing site, which allows users to share six-second long videos. Instagram responded to the popularity of Vine videos earlier this year when it added the ability to record 15-second long filtered videos to its app. Vine also recently provided a brief demonstration of its official Windows Phone app, which it intends to release in the near future.

Therefore, third-party developers such as Gray and Hyun are doing Microsoft a huge service by filling the gaps in the Windows Phone ecosystem by using APIs to build dedicated mobile apps, which have no first-party support. However, this can be both a blessing and a curse -- whereas Instance and 6tag are high-quality apps, there are also plenty of poorly made apps, which simply try to wrap mobile sites into an app.

Some steep challenges ahead
Although upcoming Instagram and Vine apps will raise Windows Phone's profile among smartphones, it still faces some daunting odds, as seen in the following chart of second quarter global sales and available apps.

Operating system

Global market share

Apps available (approximate)

iOS

14.2%

1,000,000

Android

79%

1,000,000

Windows Phone

3.3%

120,000

BlackBerry

2.7%

250,000

Sources: Gartner, industry websites.

Moreover, the reason that Windows Phone trails iOS, Android, and even BlackBerry in the number of apps is the current pecking order of app development.

App developers will usually create an app first for iOS, although it isn't the most popular mobile platform. The reason is simple -- iOS devices (iPhones and iPads) all have identical software and hardware configurations. This means that it is much easier to develop and test apps on iOS than it is to develop an app on Android, which operates across a fragmented universe of hardware configurations.

Therefore, if an app proves to be popular on iOS, the developers will then port it over to Android, knowing that it will be worth the effort. For an app to reach a Windows Phone, it usually has to go through both steps before it is even considered to be ported to Microsoft's tiny 3% market share.

Android and iOS users are also becoming dependent on the cloud-based ecosystems offered by Google and Apple, whereas Microsoft's ecosystem (Live, Office365, Skydrive) is comparatively weaker.

Microsoft is keenly aware of these weaknesses, which it tried to fix with cash earlier this year by paying developers to develop apps for Windows Phone 8 for a limited time. Microsoft even launched two app migration tools to help iOS and Android users find matching or comparable apps on Windows Phone to ease the transition between systems.

A final ironic thought
There is a bitter irony in Microsoft's current mobile struggles. For years, the company has thrived on selling closed-source software such as Windows and Office to users, while calling open-source operating systems such as Linux a "cancer".

Today, as Microsoft's mobile business treads water in hopes that other developers will follow Instagram and Vine and bring their apps to Windows Phone, independent third-party developers are filling in the holes with arguably superior apps, which would not have been possible if not for open-source web APIs.

It's still to early to pass judgment on the future of the Windows Phone. It will never be able to compete toe-to-toe with Apple or Google, but it might just hold on to enough of a niche market to remain relevant. Until then, Microsoft will have to depend on dedicated developers to pull it through this rough patch.