I got this case about 3 weeks ago and it just doesn't perform. It's almost I got a knockoff (but I ordered it from their site, not from ebay, and even mailed with them!).
1) One corner is put together with hot glue protruding (top right when looking from the front - can put up a photo later)
2) it dies in 1 hour when I use the phone heavily (and it doesn't draw more than 500mA from the battery at any time, so that means the capacity is something like 500mAh!!!)
Btw even if somebody here got 5 hours of screen time with the battery case alone - even that would be just 2500mAh. It is supposed to last a lot more (something like 6-7 hours), so with a fully charged internal battery you should get about 9-10 hours of on screen time. Efficiency of discharging the battery is in case of LiOn quite good, so we should be expecting about 3500mAh "real" capacity from the 3800mAh pack.
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