Here's a scoop for you - the killer app for Apple's upcoming tablet computer is already available. In fact, it was first released in 2002. It's Sketchbook Pro by Autodesk, formerly Alias. 

Sketchbook was designed to be used with the first generation of tablet computers and operating systems. But we all know the first gen tablets were an abysmal failure. Sales tanked and any tablet-specific app followed that lead. When Autodesk acquired Alias in 2005, they even discontinued Sketchbook.  It was resurrected in 2008 with a new version, specifically designed for the Mac OS.

With the demise of the tablet PC, creative professionals continued to use Sketchbook using digitizer tablets. Still, the application remained very much a niche product. With the iPhone, Sketchbook made a bit of a comeback with over million downloads at $2.99 each. With the limited canvas size and lack of pen input, Sketchbook Mobile is, like most iPhone apps, a bit of a toy.  Now with the impending launch of the Apple tablet, Sketchbook is ready for serious business and creative use.

So what exactly is it? Sketchbook is a drawing application with an innovative, intuitive interface and support for pressure sensitive input. Like a real pen or marker, the harder you push down, the heavier the line. Like Photoshop, Sketchbook supports layers. You can use the layers like digital vellum paper, making edits to one layer at a time. 

The interface is a bit of genius. You use gestures with the pen to change brushes, colors, etc. This way, your pen never leaves the canvas. There are no menus to navigate and no need for a keyboard. Since there's no keyboard on the Apple tablet, this sounds like a match made in heaven. Here's a more detailed review of Sketchbook.

In 2003, Alias held contests for Sketchbook artists. The results blew me away. The feedback from the artists was overwhelmingly positive. Comments like "You'll have to pry Sketchbook from my cold, dead hands." were common. Some examples from those contests live on in this Flikr gallery.

Copyright 2006 by flikr user suzi54241

A drawing application. Big deal. In the hands of the right person, this application absolutely kills. Basically take any situation where pen and paper would be used and replace it with Sketchbook. Illustration, storyboarding, presentations, annotation - Sketchbook takes the process to a new level.

If I sound like too much of a cheerleader, that might be because I used to work at Alias and used Sketchbood daily. And I am no artist. I used it for sales presentations. Using my Acer tablet PC, I would flip through slides with a flick of the pen. Then I would annotate and make notes right on top of the slides. Customers loved it. 

But I suspect annotating presentations won't qualify as a killer app. In fact, I'm sure the Apple tablet OS will have that capability built-in and it will work with any application.

What will make Sketchbook really take off is if Autodesk moves forward with a plan that was only just talked about in product development circles while I was at Alias. The idea was to launch a series of interactive tutorials and workbooks that used the unique Sketchbook interface to teach drawing and illustration - making it accessible to the masses. The tutorials would take you from stick figures to being a credible artist. Think of it as Garageband for drawing.

This got me really excited because, like playing the piano or French cooking, drawing is a skill that seems very accessible. I think I can learn it if I only had the right tools and the right teacher. With the Apple tablet, I may have the right tool. With Sketchbook, I may have the right teacher.