Correction. Zenfone 5's battery used to suck with Android Jellybean. Kitkat seems to have solved Zenfone 5's battery problems for good. My zenfone 5 now lasts almost a day with only 70 % charging. Also screen on time while browsing has improved significantly(As in earlier I used to get only 2.30 to 3 hours screen on time while web browsing but right now getting more than 4 hours).
Dear Ronnie, Thanks for your comments. May be you are right but I still not buying Zen Phone. After going through what you said I searching Mobiles again and this time I am looking for LG g3 Stylus. Of course it has Media Tek procy but Battery is 3000mAh.
I am not into games at all on mobiles. I wish I able to decide between this two... HTC 820 and LG G3 stylus might look into Samsung Note 3 also.