One of the great things about the Samsung Galaxy S3 is that you can replace the battery. This is a great feature because after enough charge cycles, Lithium ion batteries will degrade and be incapable of retaining the full rated charge. Additionally, a spare battery is one of the best ways to extend the daily life of your phone. When the first battery dies down, simply turn off the phone, pop the cover off the back, and swap out the battery.
This is an exact replacement battery for the Samsung Galaxy S3, rated at 3.7 VDC with 2100mAh of storage capacity.
Note that this battery lacks the internal antenna of the Samsung OEM battery and therefore does not support the NFC (Near Field Communications) feature.
Coming soon is a charging cradle for the Galaxy S3, which can charge the phone with or without an installed phone case and which has a slot for charging this, and the original Samsung, battery!