Regarding battery life I always wondered why the "clock" part of the display couldn't be passive.
Well, by using OLED screens, particularly with anti-relfection tech like that of Nokia (see "ClearBlack"), even a low-power iWatch could continuously and actively display the time with white numbers on a black background.
On the OLED-based Nokia N8 and 808, this all work wonderfully. Those phones don't really need more frequent recharges if you just leave the default "clock is always displayed" functionality intact. Paired with a tech like Nokia's ClearBlack screen (which is still the best active color screen WRT outdoor use), those clocks are perfectly readable even in bright sunlight.
That is, it is certainly feasible to have an always-on watch if, say, a recharge every 32 hours (assuming an at least 500-800 mAh battery - both Nokias have an 1400 mAh one) is acceptable.
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Those are fighting words mister. Back up and get ready to draw.
Regrettably, Apple is clearly behind the competitors in many respects:
- OIS
- stereo or even 5.1 (see Nokia 1520 / 930) audio recording in video
- high-dynamics audio recording perfectly usable even in loud rock concerts (see Nokia 808) - in those, all iPhones miserably fail due to distortion
- NFC (absolutely wonderful and useful even in "old" models like the early 2012 Nokia 808)
- Qi (gorgeous on the Nexus 7 2013 and a lot other devices)
- flawless HDMI output (that of Lightning is a joke)
- OLED (it does have some serious advantages over LCD; see my above post on always-displayed clocks / status and the like)
etc.