The system works by mimicking the traditional phone keypad, with the number five in the center and the other numbers arrayed around it. But since the screen has no physical keys, the software pops up the keypad wherever the user touches it. Wherever the finger makes contact becomes a five; slide the finger upwards and release, and it's a two; slide it downwards, it's an eight, etc. The user can enter a whole phone number by tapping, sliding, and releasing, all without having to look at the screen, since wherever the user taps becomes the keypad.

It's a perfect embodiment of that old adage about turning a weakness into a strength: the downside of a touchscreen device is the lack of physical controls--but that also means you can put the controls wherever you want. It's a simple yet brilliant solution to dealing with accessibility on the touchscreen smartphones.

Of course, given that Google has developed this system, it's uncertain whether or not Apple could take advantage of it for the iPhone. But the idea of making the user control the interface based on where they make contact with the touchscreen could still be a powerful idea. Imagine a visually-impaired user not having to try and figure out where the iPhone's "Slide to unlock" bar is. Instead, they simply place their finger on the touchscreen, swipe it across, and the phone is unlocked.

Google's spending a lot of time trying to figure out how to make a touchscreen interface work for vision-impaired users; the company has launched a whole devoted to exploring this and other ideas, like talking dialers and voice-synthesized directions. And since the Android OS is open source, .

It seems likely that Apple is working on its own accessibility solutions, though it's impossible to know since it's enshrouded in the Cupertino cone of silence. But hopefully the Apple engineers have come up with some similarly smart ideas for dealing with the challenges so many people face day-in, day-out.