Camera shutter buttons have a two-stop action. Half-press them to
lock focus and aperture settings, fully press them to take the
picture. There’s a delightful tactile indent at the half-way
mark so that your fingers know what’s going on. Let’s borrow
this two-stop action for the home button. Press half-way to go to
the app’s main screen, all the way to go to the phone’s main
screen. If you need to fully escape mash the button. If you just
want to head back to the main-screen of the app, tap lightly. You
can easily convert a light-press into a heavy-press mid-action.
It’s as naturally a mapping as you are going to get.
That’s a clever idea. And he’s right, that the two-stop shutter button on cameras is a terrific design. (I think the only companies that care as much as Apple does about the feel of buttons are the top camera makers. I love the feel of the shutter buttons on both my Canon 5D and Ricoh GR-D.)
But I think he’s solving a problem that doesn’t exist:
If you sit and watch people use an iPhone there’s a mistake made
often and reliably: They hit the home button when they mean to
just go back to the app’s main screen.
I don’t see people doing this. The half-press on a camera shutter serves an essential purpose. Creating a “half-press to go back to the current app’s root level” iOS home button would serve a purpose, but I don’t think it’d be worth the cost in additional complexity. How many people don’t understand the two-stop shutters on their cameras? (My guess: lots.) Plus, it would create a small exception to one of the key design tenets of iOS: when you’re in an app, everything you can do in that app is done on-screen.
Update: Lots of email and tweets from DF readers who say the problem does exist — that they frequently press the home button when they want to get back the root level of the current app. I still don’t think Raskin’s two-state home button is a good solution, but it’s worth pointing out that this does seem to be a problem for some people.
★ Thursday, 23 December 2010