Galaxy S3 Battery issue

I’ve had this phone for over five months now and the battery life has gone from bad to worse. I’m not a heavy user. I only use whatsapp, texting app, facebook and phone on a regular basis. Somehow I can’t even get 6 hours of battery out of it.

Before I go to sleep I force close all running applications and leave the battery around 50-60%. When I wake up the battery is down to 20% or less. Is this normal? I’ve noticed the problem getting worse ever since I upgraded to Jelly bean. Any help?

Re: Galaxy S3 Battery issue

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