But how come heads-up displays have never come to market in a serious way? I'm not counting Glass, by the way, given the focus on sharing rather than using.
I recall one pioneer from MIT bashed glass, pointing to his experience with having a single image in a different focus area/off-center as being uncomfortable for prolonged used (or maybe even harmful).
So that might be one reason (similar to how everyone realized in the 90s that VR made people throw up -- no market).
As for a smart-rod -- I really liked Canonical's push towards a viable use-as-phone-use-as-computer OS. It's an obvious idea that I think is already "proven" by stick-pcs and chromebooks. The cpu of a previous-generation smart-phone is enough for many tasks.
Another "proof" is what's happening with Samsung's Gear VR IMNHO, eg: http://vrjam.challengepost.com/updates/3462-meet-your-mobile...
Not sure if VR might not actually be an area where going wireless might break down though -- Oculus has spent a lot of effort getting the latency down. Still it seems it should be possible to do a lot of the 3d stuff along with head tracking in the head-set, and do more complicated physics modelling on a more powerful device.
Either way, I'm hopeful that we'll see more meaningful separation of devices as bluetooth (as I understand it) keeps getting support for lower power in one end, and higher bandwidth in the other.
It does make sense to carry the things that comprise a "smart phone" (as above, +powerful cpu that can scale down to conserve power, gpu, screen/hud/display, camera(s), low-power local-area digital radio (eg: bluetooth), touchscreen (or drawing surface/digitizer), text-input (keyboard), gps, interface for connecting 4k+ display, possibly direct-attached storage), along with a headset, preferably wireless.
I just don't see why this should all be forced into one unit. I'm not sure how much power miracast would require -- but could it really be more than what the led-lit touch-screen uses? Because surely it'd be easier to have big battery+wlan/miracast/bluetooth/cpu stuffed in your pocket, and a small display+touch+bluetooth device on your wrist, with the option to pull out a phablet-sized hi-res touch-screen with it's own battery, but only miracast+bluetooth (maybe a gpu)?
The "smart stick" (the smarphone less the camera/screen/mic) could probably be made to fit more nicely in a pocket if there was no need for a display.
Shape it like a rod, add a powerful vibrator and the thing would even be dual-use ;-) (seriously, though - if it's intended to be kept in a pocket, a vibrator might make sense, as well as a couple of status leds).
The screen is going to be a bit clunky anyway (unless it folds/rolls up) - so no real issue to add a dedicated battery for it.
Maybe I should file a patent for "smart rod".