Originally Posted by JadeAmineHa
New phone will need about 3-6 full charge cycles to stabilize
what you can do in the meantime is get a better battery monitor app like GSAM
from Play store.
Also in settings / apps / All - you can disable /uninstall all the crap a new phone comes with. I use to have a list of whats safe to disable on my AT&T One I'll look for it. generally anything with your carriers name in it can be disabled and google junk like google news / google games / chrome / gmail / hangouts / google+ can all be disabled if your not using them. lots of people use Greenify
...I have never had the need for it.
HTC One 32 GB AT&T