[VLM]

"I might prefer it clipped to my sleeve or in a shirt pocket."

COTS "Sony Ericsson liveview bluetooth phone remote". $25 from amazon, eligible for free prime shipping too. Comes with a clip holder and a watch holder.

UI is a fail, also charging. Oh and its buggy and the battery life is supposedly dismal. Aside from the 99 other things it can do when its actually working, which is why the UI fails, it can act as a music player remote (hit pause, etc). I wanted one for in my car as a simple remote when I'm listening to music. The UI doesn't do "simple" and is worse than just fumbling around with the phone. Also charging issues in the car. Oh well.

The biggest problem with bluetooth watches and phones is all the marketing is front loaded on R+D, everyone hears about "might be sold next year". No marketing at or beyond launch, no one knows there's a zillion already available. It doesn't help that whats delivered is usually an epic fail if GOOG shipped something that merely met its advertised specs, unfortunately that in itself would be revolutionary in the bluetooth watch field. GOOG is good at that, look a the nexus line, its basically an honest device without the shovelware and thats all you need to beat the competition who have dishonest claims and chock full of shovelware.

[Someone]

In this case, it is not just a matter of good execution. The first successful product also must solve the 'why put something on your arm again' problem.

If I had to direct designers, I would send them away with something like 'display that communicates wirelessly with a master device, as thick and as durable as a tattoo, one month battery life, input device desirable, but optional'.

Nobody would meet those requirements, but it helps setting the goalposts. It definitely would direct them away from the one cm or so thick design in the article being discussed.