Apple's (AAPL -0.57%) Worldwide Developers Conference stole the show among yesterday's tech storylines, and rightfully so.

As investors become increasingly excited about what Apple has in store in the second half of its fiscal year, the expectations for Apple's much-watched event were sky high. Even after the euphoria surrounding Apple's blowout earning report in April subsided, Apple's shares

Source: Apple

still crept up throughout the month of May.

Although many had hoped Apple might unveil some kind of new hardware at yesterday's keynote address, the company instead opted, as is typically the case at WWDC, to focus heavily on the software side of things. In particular, Apple made a number of moves aimed at reaffirming the tech giant's commitment to its massive body of developers.

And as other tech titans like Google (GOOG 0.37%) (GOOGL 0.35%) court developers, too, it appears Apple should be well-served by yesterday's emphasis on this oft-overlooked community.

Apple woos developers
Perhaps the most important move of Apple's many developer-oriented moves was the launch of its Swift programming language.

With Swift, Apple promised to remove many of the headaches, especially compatibilities issues, that developers can encounter when coding in popular languages C and especially Objective-C, which forms the basis of Apple's OSX and iOS operating systems. As Apple VP of software engineering Craig Federighi put it when introducing the new language, Swift eliminates the "baggage" of Objective-C programming -- news that reportedly had the bulk of developers in the audience cheering on their feet. 

Beyond Swift, Apple also introduced an improved search feature for its App Store that it promised would make it easier for end-users to find and buy developers' applications, another big win in terms of incentivizing developers to stick with Apple's ecosystem. Apple also enabled third-party development for some of its existing hardware, such as its touch-ID home button on the iPhone 5s. And the introduction of new development verticals, such as its HomeKit smart home platform and Health wellness app, will also create new software opportunities for developers to target.

Why Apple investors should care
Although it's easy for investors to overlook or dismiss these moves from Apple, they're actually intimately tied to Apple's financial success.

Apple mints its billion in quarterly profits largely on the strength of iPhone and iPad sales. And one of the major reasons individuals and enterprises purchase Apple's premium products, aside from image or brand cache, is the software or applications they're able to access. Take that away, or even shift the advantage away from Apple toward, say, Google, and the effect could prove more pronounced over time than many realize.

Google has been gaining steam as a platform for developers lately. Google launched its own version of Apple's WWDC, which Google calls Google I/O, in 2008 and has been increasingly courting this key constituency the past several years. In 2012, Google overhauled its Google Play app store in order to create improved commercial opportunities for development on Android. And likewise, Google also introduced a new suite of developers tools at last year's Google I/O conference as well. Take it to the bank that Google will try to once again increase the value proposition it offers developers to tap into its absolutely massive base of installed devices once more at this year's Google I/O, which happens June 25-26.

At the end of the day, though, Apple remains arguably the most attractive platform for developers. According to app-tracking site App Annie, apps sold on Apple's App Store are a full 85% more lucrative than on Google Play, even as Google Play has overtaken Apple's App Store in terms of number of downloads in the past several quarters.

Former Microsoft CEO Steve Ballmer was perhaps overly zealous in his passion for developers (if you don't know what I'm talking about, Google it), but he was nonetheless correct about their importance to an ecosystem's overall health. And with the suite of moves that Apple unveiled yesterday should help maintain, if not increase, the value proposition that Apple offers to its massive body of programmers, and that's something Apple investors everywhere should be cheering today.