Marco Arment:

But why do we need “smart” watches or face-mounted computers like Google Glass? They have radically different hardware and software needs than smartphones, yet they don’t offer much more utility. They’re also always with you, but not significantly more than smartphones. They come with major costs in fashion and creepiness. They’re yet more devices that need to be bought, learned, maintained, and charged every night. Most fatally, nearly everything they do that has mass appeal and real-world utility can be done by a smartphone well enough or better. And if we’ve learned anything in the consumer-tech business, it’s that “good enough” usually wins.

This is exactly right and I think we can take it one step further.

Glass users will still need a smartphone. Glass will never offer the singular mobile computer utility that a smartphone offers. How many people would be able to use Glass as their primary computer? In contrast, how many people are able to use their iPhone as their primary computer?

For now and in the foreseeable future, wearable computers are inherently restrained by their physical form. You can't type lengthy emails, formulate business proposals or create high quality media on wearable computers. Can you imagine someone dictating an essay to their wristwatch? Even Google's Glass website doesn't mention a single productive use for Glass. Glass is foundationally social. Smartphones have the potential for far more than just social.

Having said that, typing an essay on a smartphone isn't any fun either. But at least you can. You can even hook up a bluetooth keyboard if the touch screen is insufficient. As Marco clearly states, the smartphone has incredible untapped potential — potential that makes it the best choice for mobile computing going forward.

Apple isn't stupid. I doubt they are wholeheartedly developing hardware that is inherently restrained. And if they are, I'm sure they have created something we haven't imagined yet.

Sidenote: How beautiful is Marco's use of Ideal Sans? The new look is gorgeous.