To test things out, I am threw that Snapdragon battery app from Qualcomm on my Nexus 5 and the wife's... Our use is totally different (I use mine extensively throughout the course of the day, hers sits in her bag untouched most of the time. So two use cases; moderate and light usage.
I have a good feel as to the normal draws on my 5, so I'll be curious of the app actually does anything useful or just placebos the heck out of me... of course, it could be worse... there's a very well known battery 'saver' out there that pretty much zero sums it (whatever batter savings it generates gets used up by its own functions) on a good day.... and typically increases consumption.
We'll soon see.