Apple CEO Tim Cook introduces the iPad Air 2 last year. Image Source: Flickr user Maria Elena.

For Apple's (NASDAQ:AAPL) huge developer network, early June is a second Christmas of sorts. This year, from June 8-12, thousands are tuning into Apple's Worldwide Developers Conference, or WWDC, streaming sessions, while roughly 5,000 have made the annual pilgrimage to Cupertino for live participation.

Analysts and investors, however, have a somewhat different focus for the conference. While Apple's software and ecosystem are top-notch, particularly at the mobile level, the company generally monetizes its software through hardware sales, so it is important to look upon software upgrades in terms of hardware differentiation and improvement. Simply put, will iOS 9 make more prospective customers buy iDevices instead of Android devices?

A tale of two devices
When it comes to devices, there's a definite schism in Apple's hardware sales. On one hand, Apple's iPhone blew past expectations by posting two straight quarters of 50%-plus year-over-year revenue growth. Then there is Apple's iPad sales:

Source: Apple 10-Qs. Revenue figures in millions. iPad revenue as percentage of total calculation = [iPad revenue/(iPad revenue + total revenue ex-iPad)]. 

As you can see, for the iPad the sales trend hasn't been so kind. In fact, over the past year there has been a strong linear relationship between time and falling iPad sales. If the year-over-year trend continues, expect the iPad to register another sub-$5.5 billion sales figure in Apple's third fiscal quarter. Of course, a trend isn't a destiny, but some sort of catalyst -- internal or external -- is generally needed to reverse its trajectory. For Apple investors, WWDC is an opportunity to proverbially peek behind the curtain for new internal catalysts. 

Apple is going split screen
If anything, it appears Apple is bringing a productivity focus to the iPad with its iOS 9 moves. The headline feature change was the ability to place the unit into split-screen mode. For years, Apple has faced criticism from competitors and technology aficionados for lacking this functionality. High-end competitors Samsung and Microsoft have offered this feature for years. For Apple, this is more of a catch-up feature than a differentiator; nonetheless, the feature is needed to improve productivity.

Apple has also added a feature called SlideOver and picture-in-picture designed to enhance productivity. That makes sense, after tremendous growth through in its first few years,, including selling 100 million units in the first two and a half years on the market, Apple's apparent answer to the sales slowdown seems to be more focus on the enterprise side of the business. Most notably, the company has partnered with IBM for a series of enterprise-focused apps. These features should work even better on a larger-screen, enterprise-focused model.

Apple could go even bigger for iPad sales
Apple still commands the enterprise market: Good Technology found its iPad took 81% market share in enterprise tablet activations in the first calendar quarter of 2015. That was down from 92% in last year's corresponding quarter, however, as competition has increased in this key market. While not yet confirmed, many expect Apple to release a 12.9-inch iPad dubbed the iPad Pro to build upon its enterprise-related market share.

If so, these new features will fit nicely with a large screen and sustain Apple's tradition of combining compelling features with strong hardware. In the end, the iPad's new features aren't quite a game changer, but this is a solid evolution in an underperforming product line.