IPhone 4s battery suddenly drains?

In the last few days, all of a sudden, my iPhone battery drains extremely fast. Usually when it is in lock mode, it doesn't drain at all. Now it goes down fast even when the phone is not in use. And it is also taking longer to charge. Has Apple uploaded some new software recently that would screw this up?
I already did a reset, but that doesn't seem to work. Are there any apps that can improve battery life?

I'm having some issues with my 4s, it will only charge when it is completely off and will not get recognized by iTunes when i plug it in to my mac. I'm running 5.1.1 I'm an apple developer and should be able to figure out what is wrong but can't.

Well charging your iphone overnight can cause dis so if your doing dat I reconmand you to stop now but if not den your. Charging your phone to often

Wow Brandon is a genius +1

  • MY IPHONE TURNS ON IN MY LOCKER AND DRAINS Battery Ok so on the bus ride to school i listen to music on my iphone 4. When i get to school i turn off my iphone, i always double check! I put it in my locker than go to class. After school i come back and my iphone is at freaking 4% and its on! I don't know what is going on!
  • My iPhone 5 battery drains during lock? Whenever I sleep, I never charge my iPhone, so it's basically next to me on lock. I think I slept to it being 38%. I slept for 11 hours (yup, I'm a potato.don't worry, this was only yesterday) and the next morning, I woke to the battery being like 25%. Just wanted to know if this is normal?
  • My iPhone 4S battery drains really fast? So I got my new iPhone like 2-3 weeks ago and it has such a bad battery. It went from 59%-25% in th matter of not even 2 hours and I checked the usage at 1% and it only had about 5 hours 40 minute usage and 19 hours standby. Is there anyway I can fix this?
  • My battery on my iphone 4s drains really fast? Since i've had my iphone 4s i've noticed it has very terrible battery life and also it heats up when i play games or watch videos does anyone have any tips or advice on how to deal with this problem? Ps i already have tries turning of 3g and push mail and that to save battery but it does not have an affect