It is no secret that Microsoft's mobile ambitions have one persistent and seemingly inescapable chink in its ever-morphing armor: the app gap.

It seems that virtually every review of a great Microsoft product or even glowing blog posts about the benefits and progress of Windows 10, ends with an obligatory reminder that in comparison to iOS and Android, there is a substantial app deficit in the Windows ecosystem. The issue is so profound that not only are critics of the platform trumpeting this message, but Windows enthusiasts have also begun to bend under the weight of the truth of the matter. For context Google's and Apple's platforms boast at least a reported 1.5 million apps. In comparison, Microsoft's growing platform has just one-third the apps Google Play and the App Store boast. At nearly half a million apps Microsoft is desperately working, particularly during their period of retrenchment from the general smartphone market, to close this gap. This task is not a simple endeavor. As it requires not only the technical and strategic efforts Microsoft puts forth, but also the voluntary commitment of developers and consumers who can perceive Microsoft's vision, it is a profound challenge. Best VPN providers 2020: Learn about ExpressVPN, NordVPN & more

As this series has highlighted, Microsoft is currently in a state of retrenchment from the general smartphone space as the company nurtures various aspects of its ecosystem to ensure a successful rebirth into that consumer space. Refining the OS, building OEM partnerships and developing the tools, infrastructure and relationships for a rich app ecosystem are all part of this "gestation" stage of Microsoft's mobile strategy. In this final installment of the "Windows Phone isn't dead series" we will stare the "elephant in the room" or ecosystem, the app gap, square in the eyes. With an unwavering and candid approach, we will tackle this massive problem with an equally massive piece to culminate this series. I will share with you answers Microsoft provided to some of my inquiries. We will also delve into Microsoft's app Bridge strategy and provide further analysis as to the possible direction the company's purchase of Xamarin may take them in their quest to close the app gap. That said, if the app Bridges and the Xamarin purchase ultimately yield what I believe Microsoft is aiming for, Redmond may actually change the game in the process. A developer's dilemma is Microsoft's dilemma Any Windows phone user that has been part of Microsoft's ecosystem for a reasonable amount of time has seen many popular apps come to the platform. Instagram, Candy Crush Uber, Twitter, Shazam, Netflix, Dropbox, Hulu, the recently announced Starbucks app and others are all popular apps whose arrival added validity to the platform. Sadly, we have also seen developers like Tumbler and others end their support. Less frequently we are surprised and excited when we see apps like Bank of America, which have left the platform return as more evolved Universal Windows 10 versions of their previous iterations. Of course our hope is that most developers will remake their apps as Universal Windows apps. The sad and candid truth, however, is that many developers have found developing for Windows problematic. Some who invested in Microsoft's mobile efforts years ago have found the trek toward a unified platform jarring and inconsistent. Transitioning from Windows Mobile to Windows Phone 7/7.5/7.8, to Windows Phone 8/8.1 and ultimately to Windows 10 Microsoft's mobile strategy has morphed the platform through various iterations where the continuity of support has been disrupted for users and developers alike. Consequently, some developers have deemed the investment in maintaining or continuing their app to be too much for a return on investment (ROI) that was too little.

This reality has resulted in both a selection of many Windows apps that are a pale representation of their iOS and Android counterparts as well as the previously mentioned exodus of some apps from the platform. Other developers who have never made a Windows Phone app look at the platforms minuscule market share and deem the user base not worth the financial and human resources necessary to even initiate development of an app. These concerns are not without merit. Some company's limited resources allow them to invest in the skill sets needed to develop for iOS (Objective-C) and/or Android (Java and C++). As such the return on investment for developing for what has (before Windows 10) been a much smaller platform in Windows Phone may not have justified moving forward with a Windows Phone app. This analysis, of course, is not applicable to all companies that have no interest in the platform. Think SnapChat. But it seems to be the story that most companies who have not developed an app or who have withdrawn their apps have told. Microsoft would like to change that story. This juncture in Microsoft's mobile strategy is where the app Bridges come in. Microsoft designed these tools as a direct response to the concerns expressed by developers who have left or have never embraced Windows. Microsoft's Kevin Gallo stated the goals of the app Bridges this way: "Our goal is to make it easy for developers of all sizes to bring existing code to the one billion devices we expect to see running Windows 10 in the next few years" … HTML/JavaScript, .NET and Win32, Java/C+ + and Objective-C bring their code to Windows, and provide a way to integrate with Universal Windows Platform capabilities." That said, the candid question developers that have found success developing for other platforms may have is, "Why should they use the Bridges at all?" To get to the other side

By giving developers the tools to reuse existing code, Microsoft effectively eliminates the barriers of the additional costs a company would incur if required to hire a Windows developer. This strategy also reduces the time resource necessary to build and maintain a Windows Universal app since the developer the company has already invested in can, for example, reuse his iOS (Objective-C) code. The benefits of this reality are compounded by the fact that Windows 10 is the final version of Windows. As such developers have the assurance that there will not be shifts in the platform that essentially "break" the apps they've invested in as was the case as Microsoft's mobile platform evolved toward Windows 10. For those developers that have felt burned by the shifts in the platform as it grew toward the unified core, our arrival now at Windows 10 may present the assurance they've needed to venture another app on the platform. That said many Windows fans and industry watchers would like to know the status of these Bridges. What exactly are they and are they yielding the fruits Microsoft desires? Microsoft's Kevin Gallo recently provided the following update: Westminster - The Web Bridge Hosted Web Apps helps bring HTML and JavaScript web-based apps to the Windows Store (and) shipped as part of the standard Windows 10 SDK in July and ..(has)…seen adoption from companies such as Shazam and Yahoo.

Centennial - helps bring existing Win32 and .NET-based apps to the Windows Store and is in testing with a set of developers now. Microsoft will have an early iteration of the tools soon, and then they'll expand the program and support a broader range of developers.

Islandwood - enables developers to bring iOS (Objective-C) apps to the Windows Store, (and) was released to GitHub as an open source project in August and Microsoft has been releasing updates to it frequently. Microsoft recently released an update which included the first ARM32 preview compiler drop. "Success to us is about our customers and developers loving Windows 10." Astoria – Microsoft has received and carefully considered feedback and decided that they would focus their efforts on the Windows Bridge for iOS and make it the single Bridge option for bringing mobile code to all Windows 10 devices, including Xbox and PCs. Microsoft adds: We initially focused on API coverage for game developers, but we are expanding our API coverage for all app types by adding support for additional frameworks, etc. The early signs of adoption of the Westminster Bridge, the testing of Centennial with select developers with planned expansion and the release of Islandwood as an open source project on GitHub reveals Microsoft's progress with its app Bridge strategy. Of course, a firm foundation for these tools is crucial if the application of the tools is to be successful. When I asked Microsoft how they measure the success of the Bridges a spokesperson shared: "Ultimately, we want people—customers and developers alike—to love the experience on Windows. Success to us is about our customers and developers loving Windows 10." Developers, developers developers

If bringing developers on board was as simple as shouting "developers, developers developers," Microsoft's CEO Satya Nadella and Steve Ballmer before him, would certainly have had every Microsoft employee rehearsing that chant daily. The reality, however, is that to entice developers (particularly to an underdog platform) the approach must be comprehensive. Microsoft has therefore invested in a multipoint approach - a modification of the infrastructure - to make developing for Windows a worthwhile investment. By creating a unified platform that extends the range of devices a developer can target, improving opportunities for monetizing on apps, expanding carrier billing to Windows PCs and tablets, improving app discoverability, and simplifying the app submission process Microsoft is taking a holistic approach to reaching developers. One Microsoft spokesperson expresses what is likely the most profound and easily communicated incentive: "One billion Windows 10 devices creates a fantastic opportunity for developers as Windows 10 extends the universal apps model making it easier for developers to build apps that span Windows devices. " Since its July 2015 release, Microsoft is 200 million installs into its two-year one billion Windows 10 install goal. This growing install base and the designated goal are the numbers Microsoft loves to share when communicating the benefits of developing for Windows. And for good reason. The Universal Windows platform extends a developer's audience beyond tens of millions of Windows phones to hundreds of millions and eventually more than one billion Windows devices including the growing category of mobile devices like 2-in-1's. This massive audience, in conjunction with the Bridge tools positions developers, to vastly increase their monetization opportunities. Getting the attention of developers with these winning numbers, however, is not enough. If the process of getting an app from a developer's mind to the Windows Store is arduous, Microsoft could lose the commitment of developers in the long run. Easing the process

Microsoft has simplified the submission and management flow of apps to the Store to get them up and running quickly and efficiently. Of course, once an app is in the store discoverability and engagement is the next hurdle. Microsoft shares the following regarding how the firm helps developers leap that hurdle: "Windows 10 extends the developer opportunity both by targeting a wider range of devices through a common Windows Store and by creating more ways for end-customers to discover and engage with apps." Since the launch of Windows 10 with its "Start Menu-positioned" Store, the Store has had over 3 billion visits; developers are receiving 4.5 times more revenue, and app engagement has seen a measurable increase. Microsoft's modifications to the Store ensures that once a developer's UWP app reaches the Store, there will be an increased level of discoverability, greater visibility and potentially higher engagement compared to apps written for Windows Phone 8/8.1. Microsoft's Todd Brix expounded on what this data means for the company's commitment to developers this way: Both the growth of Windows 10 customer base and the increase in customer engagement (both with the Store and with the apps themselves) will enable us to deliver on our promise of providing a platform where developers can find growing success. Naturally not all regions have equal access to popular payment methods such as credit cards. Thus, if a developer's apps were discoverable but inaccessible to a large percentage of the audience, the efforts mentioned above to showcase those apps would be moot. Thus, since 88% of the world does not use credit cards Microsoft has extended carrier billing to PCs and tablets. This decision has removed a major barrier many customers would face when attempting to access the growing pool of Windows apps. Show me the money!

To compliment the increased discoverability and additional payment options Microsoft has also improved the tools available to developers to monetize on their apps: "For developers looking to monetize their Windows 10 apps, we released the new Microsoft Universal Ad Client SDK which is available for Windows devices, including Windows 10 phones, tablets and PCs." In a nutshell, this allows developers who earn money via advertising "to grow their revenue." In the immortal words of Jerry Maguire, "Show me the money!" This allows developers who earn money via advertising to grow their revenue. Microsoft believes these infrastructure enhancements will go a long way in helping bring developers on board. I am hopeful. That said I did ask the firm about one of the most front-facing concerns expressed by many users. Namely, what type of support is offered to developers to encourage their continued development of apps (keeping them updated) once they reach Windows. A Microsoft spokesperson provided the following response: Microsoft has a long history of engaging with developers to support and accelerate the creation of compelling apps. We continue to invest in helping developers in a variety of ways including online as well as personal support, test devices, events, hands-on labs, training, various types of co-marketing agreements and free professional tools. From a message of a growing and massive install base that is meant to draw developers in, to structural changes that are designed to make apps successful, to ongoing developer support, Microsoft has enacted a system that aims to make Windows developers successful. One major challenge remains, however. Microsoft must change how the industry sees "phone" within Microsoft's UWP. Since the industry sees the "phone" as the primary personal computing device, and, therefore, the main purpose of app development Microsoft has to change how an entire industry of developers, consumers, OEMs, investors and writers see the position of "phone" within Microsoft's Universal Windows continuum. I asked Microsoft how they plan on doing that. Keep reading. Problems with perception

Microsoft has made an unprecedented industry move in its creation and release of the Universal Windows Platform. This ecosystem-wide shift quite literally changes how Microsoft is positioning its personal computing platform from development to user experience perspective. Whereas Apple and Google have multiple platforms for distinct device types, Microsoft has whittled its personal computing ecosystem down to one platform for all device types. This move requires a shift in thinking from developers who, for example, see developing for Apple's entire personal computing ecosystem as a task in targeting iOS, watchOS, OS X and tvOS. Similarly, developers fully invested in Google's personal computing ecosystem currently must focus on both Chrome and Android. As we have shared in the past, each of these firms has different operating systems for different device types. All personal computing devices take a front row seat in Microsoft's ecosystem. Microsoft's UWP is a cloud-first, mobile-first positioning of personal computing that frees a user's digital experiences and a developer's commitment from any single device. As such all personal computing devices, from Microsoft's perspective take a front row seat in Microsoft's ecosystem. Moreover, users have an increasing expectation that activity they begin on one device will be seamlessly accessible to them from any other device. Thus, the current phone-focused developing and UX paradigm where most developers target one device, (the phone), in a company's personal computing ecosystem, is both limiting and is not reflective of the current shift in personal computing. Consequently, Microsoft's Universal Windows Platform at its core is the only platform that allows any developer to create Universal apps that work on all device types. Apple's Continuity, by comparison, offers only a surface level user experience that moves data between some devices. Unlike the UWP, it does not provide an end-to-end solution from a development foundation to a user's experience. Thus, Microsoft's UWP is uniquely positioned to offer the industry a comprehensive solution from the development level to the user experience level that serves what is increasingly a core expectation of end users.

Developers have yet to embrace the shift from a phone-focused to an ecosystem-focused view. Developers have yet to embrace the shift from a phone-focused paradigm to an ecosystem-focused view fully. When I pressed Microsoft about what they are doing to help developers see the potential in developing for the UWP, to change the phone-focused perspective still held by many, I was given the following: Windows 10 opens all new doors to customers and developers with one platform, one store and a growing catalog of universal apps. With the free upgrade of Windows 10, we are seeing adoption of Windows 10 at the fastest rate in history, with over 200 million devices already running Windows 10. We believe this will re-energize the ecosystem, creating all new opportunities for developers… Phone is a key part of bringing Windows 10 to more people, and Microsoft will continue to focus on delivering the most productive Windows-based smartphones on the planet. Admittedly the firm was not as forthcoming as I had hoped. Given our proximity to the /BUILD Developer's Conference, however, particular information in this regard is likely being reserved for that stage. That said, with Microsoft's introduction of the UWP being only eight months old and the Mobile component having just begun its public roll out on March 17th, 2016, the nearly 10-year old phone-focused paradigm is still considerably unshaken. Microsoft is confident, however, that as hundreds of millions more Windows 10 devices are added to the 200 million already online the industry will begin to shift toward the broader personal computing ecosystem-focused view Microsoft's UWP offers. Enter Xamarin On February 24, 2016, Microsoft and Xamarin announced that the Redmond-based company would be purchasing its long-time partner who specializes in the provisioning of tools to produce cross-platform mobile apps. Xamarin's mission is summed up by Nat Friedman, the company's co-founder, in the following statement: We founded Xamarin more than 4 years ago with the mission to make native mobile development fast, easy, and fun and to help C# developers build beautiful mobile apps and reach billions of devices. We love the native iOS, Android, and Mac APIs and we love C#, and this acquisition is an ideal next step for us and for our customers. Along with partner Miguel de Icaza, Nate has led Xamarin to a level of success that has allowed the company to serve 15, 000 customers in 120 countries. They have also partnered with 1.3 million individual developers that have used the company's powerful tools.

Microsoft's and Xamarin's relationship has born the fruit of the deep integration of Xamarin into a range of Microsoft's services. Visual Studio, Microsoft Azure, Office 365 and the company's Enterprise Mobility Suite have all been integrated with Xamarin. This integration has provided "developers with an end-to-end workflow for native, secure apps across platforms." Microsoft's acquisition of Xamarin signals a pending strategy consistent with the company's ambitious goal to be the "platform" of platforms: With today's acquisition announcement we will be taking this work much further to make our world-class developer tools and services even better with deeper integration and seamless mobile app dev experiences. The combination of Xamarin, Visual Studio, Visual Studio Team Services, and Azure provides a complete mobile app dev solution that provides everything you need to develop, test, deliver and instrument mobile apps for every device. As our own Editor and Chief, Daniel Rubino put it, bridges go both ways. Microsoft's app Bridges allow developers to reuse existing code so that apps from other platforms can be brought to Windows. Xamarin's integration into the core of Microsoft's mobile app development strategy positions the company to become the provider of tools that enables developers to build apps that target all mobile platforms simultaneously. Additionally, C# the programming language at the core of Xamarin was recently reported to be the preferred language by 62% of the respondents to the Stack Overflow Developers Survey. This is where things get interesting. Analysis: Changing the Game

With the Xamarin purchase, I believe that Microsoft ultimately wants to become the platform for mobile app development. Currently, most individual developers or companies with mobile ambitions perceive developing for a mobile audience as creating an iOS and/or Android app. This general perception is the barrier that consistently cuts Windows (Phone) out of the picture. "Mobile" in the minds of most developers has become synonymous with iOS and Android. The app Bridges, though necessary and useful, cater to that particular mindset. They do little to alter the perception of developers and others in the industry regarding the position of Windows as a viable mobile platform. The idea of bridges just beckons a particular action - convert your app to a UWA - without appealing to a change in perception of Windows as a first-tier mobile objective. Allow me to explain. This requires an undoing of the broad perspective that iOS and Android are synonymous with mobile. As Microsoft pushes the Bridges they, by necessity, reinforce in the minds of the industry the inaccurate view that iOS (and Android) essentially equal "mobile." The push strengthens a secondary position of the Windows platform. It does this by petitioning developers to use the Bridges to convert their "primary mobile code" (iOS) to a form that includes this "secondary platform" (Windows) which does not occupy a dominant position in their minds as a target as a mobile platform. Microsoft needs to move the position of Windows from a secondary position to equal footing in the minds of the industry as a target for mobile development. This change in perspective requires a change, an undoing, of the general attitude that iOS and Android are synonymous with mobile. The efforts to push the UWP and the growing Windows install base, as mentioned above, are part of this picture. I believe that the other part of the picture is where Xamarin fits in.