I have noticed that if the battery drain really starts to get ridiculous, rebooting the phone has helped dramatically. I went from draining a battery in 10 hours with minimal usage (no phone calls, maybe a dozen and a half txt messages) to about 36 hours with slightly increased usage (2 phone calls, about 20 received and 20 sent text messages, opening up the Steelers football app to check highlights of the game occasionally over the course of 3 hours, opening words free to play 2 words with a friend) just by rebooting the phone.
Even right now, my main usage killer is words free, that friggen app along with the screen being on sucks the battery dry while its open. I'll edit my post and add a screenshot later. But when it was draining in ~10 hours with barely any usage, the main power user was "android os". Something's goin on in the background that's causing the battery to dwindle.
EDIT: Those screenshots: Keep in mind when reading that these figures only account for about 40% of battery drain, and that the phone was rebooted about 48 hours prior to the beginning of this battery cycle.
This is my battery usage for the last 5-6 hours, so basically since I got up this morning. The screen and words free accounts for almost 60% of it, so realistically if it had been sitting without me touching it all day it would be at about 85% battery remaining after almost 6 hours.
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Battery usage of the screen. 30% of the current battery drain for an hour of the screen being on.
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Words free battery usage. Almost 30% for a HALF HOUR of in app usage (not just it sitting in the background, but it being up on my screen. Mind you I have this app set to check back with the server every hour instead of the default 5 minutes)
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Android OS usage. The keep awake time is actually relatively low compared to what I was seeing before reboot. Before the reboot my keep awake time was nearly the same as my "time on battery" statistic.
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