I have to charge my phone every night, well I don't HAVE to but it would die at pretty early in the morning if I didn't. I heard something about your phone's signal being bad has something to do with it. I pretty much barely get signal in my house (Verizon) and Verizon gave me a network extender but it doesn't really work. I lose about 15% every night. Which isn't horrible, but I lose like 2% seemly every 10-15 minutes. And thats with barely any use (4-6 of those minutes, the device wasn't even awake.). Is this normal? Oh, and I have auto sync on but I kind of want it on, it's only for google related things, and only half of them at that.
Edit: I turn GPS off at night. I feel like it helps but it probably doesn't. My screen brightness is at like 20%.
From my experiance, I have found that leaving wifi on drains the battery more than it should. It doesn't make sense, but you should turn it off when screen goes off. I use an app called better wifi on/off which automatically turns wifi off after 10 seconds of screen off and turns it back on when unlocked.
I also think your signal strengh is causing more drain that it should be. So you should do what I do and switch to 2G when at home or wherever you are right now. When wifi gets turned off when screen is off, 2G should be efficient in letting you recieve emails/whatsapp/facebook etc.
Also should get an app called automate it pro, which will allow you to make automatic commands. I have my one dim the screen, turn off sync, turn off the radio at a certain time at night meaning the battery only drops 1 percent or 2 overnight as opposed to around 10-15%.
Also, if you dont need them, turn off google now, and go into maps and turn off the location settings. You can use the GPS whenever you need maps, but the wifi location searching seems to be more detrimental to battery.
Check your apps and try to make sure they're not updating too frequently. Also check your "sync" section in the settings and disable all you don't need and perhaps put a less frequent update interval for the ones you do need.
Finally, you can install an app called betterbatterystats and leave it to run overnight, and then check out the "partial wakelock" section to see which apps are causing your phone to constantly wake up and then try eliminate them.
Hope this helps.