Maybe u can try the following to save more battery power
1)Uninstall or disable those preloaded and google apps that u dun use
2)Go to wifi advance setting and off the ''Network notification"
and ''Scanning always available'' and when u r using wifi off ur data, if u r using
data off ur wifi, dun keep both on as it drain ur power.
3)Use asus built in Autostart manager to prevent app from
auto starting, u can allow those app that u want to be active
all the time, for eg. whatsapp
3)go to
http://www.asus.com/zentalk/forum.php?mod=viewthread&tid=58526&extra=page%3D1
follow the instruction there to help u find out which app is
always waking up ur phone and there r 2 setting there u can
tick to prevent that app from waking ur device or keeping ur
device awake.
4)Lastly use the Asus power saving feature, for myself, i'm
using the customized power saving for normal times, and set
the time for the phone to auto switch to Ultra power saving
mode for the time that u will not be using the phone for eg.
when u sleep.
Doing all the above, i managed to squeezed more battery power, thats all we can do for now, since its a well known fact that lollipop 5.0 is a battery draining os, have to wait for asus to release mashmarrow which from reviews is quite promising in the battery saving department.
Oh btw, i'm on latest 1.14.40.695_20151114 firmware and make sure all ur apps especially those preloaded apps that u will keep for use is updated.Especially asus pixelmaster camera app, i find that the latest version produced better/sharper photo quality in well lighted environment, the night shot and low light shot still not really good, got to wait for future firmware to fix that.