Since this is a smart phone we know that installing an app can cause this. Also, if GPS, WiFi and Bluetooth are on, it may not make through the day. There are tomes on the web about getting more battery time so don't install any apps, and follow CNET's article on turning off things.
-> https://www.youtube.com/watch?v=rys-jf7Icb4
More at:
http://www.cnet.com/how-to/five-settings-that-increase-battery-life-on-android-4-4-kitkat/
http://www.cnet.com/how-to/how-to-improve-battery-life-on-any-mobile-device/
Bob
My S3 Mini's battery only lasts about 5 hours. The battery tab says "Wakelock" / Media uses 95% of the battery. The phone is always "awake" (blue line continuous). Samsung has replaced the PC board and battery, but the problem continues. Can anyone plz help?

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