Since Satya Nadella took over as CEO of Microsoft (MSFT -0.74%), the company has dramatically shifted its strategy. Instead of focusing solely on Windows, other platforms are now being treated as first-class citizens. Android and iOS versions of Office have launched, for example, and have proven to be extremely popular, with over 80 million downloads on iOS alone.

While keeping its software exclusive to Windows made sense when Windows was the only platform that mattered, the changing mobile landscape has forced a change. Over 1 billion smartphones ship each year that run either Android or iOS, not to mention hundreds of millions of tablets, and ignoring those markets would have been a disaster for Microsoft in the long run.

The Windows PC is still the best-suited device for plenty of use cases, though, and one of those is developing software. In the past, Microsoft's Visual Studio integrated development environment, or IDE, has largely been aimed at developing software for Windows, but that too is now changing. With the launch of Visual Studio 2015, Microsoft is fully committed to cross-platform development, with the new IDE supporting development of Android, iOS, and even Apple Watch apps. Here's why Visual Studio 2015 is important for Microsoft.

Big changes
Visual Studio 2013, the previous version of Microsoft's IDE, gained cross-platform development features through various updates, so Visual Studio 2015 is really just a continuation of that effort. VS 2013 gained support for a preview version of Apache Cordova, for example, a set of tools that allow developers to use web-standard HTML, JavaScript, and CSS to build cross-platform smartphone applications.

VS 2015 fully integrates Cordova, and it supports cross-platform development using other programming languages as well. Native Android apps can be developed, and VS 2015 even comes with an Android emulator built on top of Microsoft's Hyper-V virtualization technology, allowing developers to quickly test and iterate their applications.

In addition to supporting cross-platform app development, Microsoft's Azure cloud platform can be utilized for the back end, regardless of the platform. New Azure services can be created, managed, and debugged directly from Visual Studio, and these services support apps running on all platforms, not just Windows. Push notifications, for example, can be sent to Android, iOS, and Windows devices through an Azure mobile service.

With Visual Studio 2015, Microsoft is trying to ensure that Windows remains the main development platform, even if the applications being developed aren't for Windows at all. And with deep support for Azure, Microsoft is aiming to make its cloud platform easy to use for developers, potentially giving it an edge over competing cloud platforms.

Giving it away
The professional and enterprise versions of Visual Studio have always been expensive, priced in the thousands of dollars, and that hasn't changed with Visual Studio 2015. Prior to late last year, Microsoft offered an Express version of Visual Studio for free, but it was missing key features like support for extensions.

This changed last November, when Microsoft announced the free Visual Studio Community 2013. Unlike the Express version, Community is fully featured, with the catch being that it can only be used by individual developers, up to five users in a non-enterprise organization, or for academic, educational, or open-source use.

The Community edition lives on in Visual Studio 2015, giving individual developers and small teams free access to all of Visual Studio's features. Previously, an individual Android developer, for example, may have been drawn to an alternative IDE -- there are plenty that support Android development on both Windows, OS X, and Linux. Now, with both full support for cross-platform development and a fully featured free version, Visual Studio is no longer at a disadvantage.

It's all about developers
The goal of all of this is to win over developers to Visual Studio, Windows, and Azure. Microsoft, as explained by Nadella in an early email to employees last year, is a productivity and platforms company. Microsoft's purpose under Nadella is to enable people and organizations to be more productive, and that's exactly what Visual Studio 2015 aims to do.

Giving Visual Studio 2015 away for free to individual developers makes sense for a few reasons. First, the enterprises of tomorrow are the individual developers of today, and getting as many developers using Visual Studio as possible is more important than a short-term boost in revenue. Second, with deep integration with Azure, Visual Studio 2015 makes a very compelling case for using Microsoft's cloud platform. Azure is a key growth area for Microsoft, and making it easy for developers to use is critical.

Windows is still important, but it's not the only major platform anymore, and Microsoft has finally come around to that reality. Microsoft has now fully embraced non-Windows platforms, both by bringing its software to Android and iOS and by making cross-platform development easy. Visual Studio 2015 is another step in the right direction for Microsoft.