What happens to existing interface design conventions when exposed to a paradigm shift? What happens when a fundamental principle upon which you've build nearly everything begins to crumble?
It's an important question to consider, because even though you may not have noticed, things are starting to change.
What's shifting, you ask? Well, before I answer perhaps a bit of history is in order. Back in the day, when the people at SRI International and Xerox PARC and elsewhere were doing the core research that resulted in the modern graphic user interface, they had a problem: how to represent the user in the metaphoric world they were developing.
Documents and folders as metaphors seemed intuitive enough, but how did one manipulate them? Just how did that virtual document get into that virtual folder? Ultimately, several core concepts were developed and eventually came together in the Alto, the first computer to use the desktop metaphor and graphical user interface. Often credited to Douglas Engelbart, they were the mouse, the button, and the pointer.
Move the mouse and the pointer on the screen moved accordingly. It was a proxy for your hand in the virtual world. Press the button, and your "hand" grabbed or poked or otherwise manipulated the virtual object your hand was resting upon, or upon which your "finger" pointed.
Now you could put that document in a "folder", or in the "trash". The metaphor worked, and was adopted it in systems like the Xerox Star, Apple's Lisa and Mac, and in Microsoft's Windows. Particularly since doing so meant that people didn't need to learn other less-easily mastered concepts like del -r c:\bak\mydoc\work\reports\0706\.
Fast forward a few decades, and you'll see that we've developed a rich ecosystem of virtual objects: documents, folders, windows, buttons of all shapes, sizes, colors, and descriptions. Icons, tabs, links, sliders, scrollbars, menubars, popups, dropdowns, radio buttons and checkboxes, lists, trees, and more. If it exists in the physical world it probably has an on-screen analogue.
And all are things that are, in one way or another, actionable.
Further, and more to the point (sorry), over the years we've developed have a rich visual language to indicate that yes, this funky-looking thing here is actionable, and that whatchamacallit there is not. The most common of these is the cursor/mouse pointer change.
Move the mouse pointer around any modern web browser, and once again our somewhat oddly-shaped "hand" appears, indicating that we're over something we can poke and that, in the poking, something interesting is likely to occur.
Part of our language is based on convention. We've learned, for example, that 3D-shaped thingies are more likely to be clickable than flat 2-dimensional ones. Such objects often even change in response to being clicked, altering color or shape, dimpling inwards when poked and outwards again when not.
Over the years our visual cues have gotten even more sophisticated and less obvious. Big buttons have become smaller. Ballooning 3D curves have become less pronounced. In fact, in many cases some of our more obvious cues have disappeared altogether.
We've grown accustomed to interface elements like rollovers or other items that change not when clicked, but when the cursor happens to move over them. Menus appear. Sliding boxes slide. Invisible elements glow or change color. Previously dormant objects spring to life and in doing so shout, "Oh! By the way, I can be poked too! Do it! Do it NOW!"
But--and now we get to the crux of the matter--what happens when there's no pointer?
Yes, this is about the iPhone. And more.
Jeff Han gave a great multi-touch demo at TED, showing huge flat touchable panels containing virtual items that can be manipulated directly. Papers that can be shuffled and set aside Minority Report-style. Photos that can be expanded and contracted with a couple of fingertips. The future of computing.
But the iPhone is here, now, and people are being asked to develop Web 2.0 applications for it.
What will those applications look like?
Continued in Part II.