On any given day, a quick check of the top-selling paid apps list in the Mac App Store will reveal Apple's Keynote, Pages and Numbers in the top ten. It's surprising, given that each of those apps was originally bundled as Apple's iWork '09 productivity suite, released in, you guessed it, January, 2009. It makes me wonder when or if we'll ever see an update to them.

The concept of "iWork '09" as a package disappeared when Apple launched the Mac App Store in 2011 and transitioned to digital software distribution. With it came a few changes: the individual components of the iWork suite became available on their own for $20 a pop. At $60 for all three, customers saved money compared to the disc price of $79. It also enabled users to buy them a la carte if they preferred.

Since then, Apple has released some perfunctory updates to each of the apps to improve support for new operating system releases and added a few functions here and there, but none of the apps have gotten a significant overhaul in over four years.

What does Apple have planned for Pages, Keynote and Numbers? Of course, no one outside of Cupertino knows for sure. Apple has, however, posted job listings for iWork engineers in recent months. So there's plainly work going on behind the scenes.

Given the continued absence of Microsoft Office on iOS - and the likely continued absence, given Microsoft's emphasis on its own Surface tablet - the iOS iWork apps continue to help Apple fill an important business software void on the iPad.

In a month Apple will unveil the newest versions of both iOS and OS X to attendees of its Worldwide Developers Conference (WWDC) in San Francisco. I'm not sure if Tim Cook will use his time on the keynote stage to show off new iWork apps, but I'm willing to bet that the announcements at the event will lay the groundwork for whatever Apple's going to do next with those apps and its iLife software, which is also getting long in the tooth.

Pages, Keynote and Numbers' position on Mac App Store's paid apps list suggests that they're still very important for Apple. But four years is eons in software development. Even Microsoft has refreshed its Office for Mac product in the intervening years. The interfaces of each of the iWork apps is sorely lacking and occasionally inconsistent with Apple's own Human Interface guidelines.

It's time Apple showed the iWork apps a little love. Hopefully the wait won't be too much longer.