galaxy s3 continues to drain power

[Android Question]

have now had 3 phones and 3 different batteries in the past two weeks....all drain within 3 hrs. Have not added any apps....??? What is going on?

 

[Rukbat]

Fully (100%) charging the batteries before using them?

Have all unnecessary radios (wifi, GPS, Bluetooth) off?

Real Samsung batteries?

If all that's true, either you have unusually bad luck or Samsung has an unusually bad production run of S3s or batteries. (I haven't heard of the last update causing this particular problem, but I wouldn't completely rule it out either.)