1) Is the battery life okay?
average each % lasts 6 mins of screen time, on 4G, brightness 30%, sync off and stuffs.
mine once hit 5hrs at 50%,100% 4G network.
that's including some usage on whatsapp too, surf Facebook on browser instead.
Facebook standalone has too many wakelocks.
2) Will it auto wake when there is SMS or whatsapp msg?
can configure. if you want minimal wakelock, install 'smart data switch pro'.
3) Is it Made in Korea?
yes but the battery.
4) How long does it take for full charge?
just leave it there unused, not more than 2hrs.