I have gotten the battery just now, and I have to say that I'm not surprised that it's a scam. I'm quite disappointed, maybe a little regret since I could've used the $20 for something more (eg. food or laser tag with friends). Please do not get duped by the reviews, while it has 5 stars all in all, Battery Pro+ reports the same 1650mAh capacity. Like others said, the higher the capacity, the thicker and heavier the battery has to be. But the battery has the exact same size (not thicker nor thinner) and weight as the stock battery, maybe a bit lighter, and has a cheap feel to it. Although it was nice of them to include a phone case, which isn't even the right model.
Battery Pro+ reports 1650mAh. This is the only app I know that reports battery capacity.
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See attached pics. (Sorry about the quality, taken from Surface RT)
There, I have taken one for the team. I'm sorry to say this, but to those people who claim to have longer battery life, it's not. I believe they scammed using psychology. It's like scratching your head just because you know the person next to you has head lice, even though they don't. Unless someone can give me an actual proof reading of the battery capacity with 2500mAh, I'm still not convinced.
I'm scared to use the battery (especially charging wirelessly, which makes the phone case quite warm and could be fire hazard). I do not plan to return the battery, god knows how much the shipping would cost to return it, probably more expensive than buying it. So I'll let this one slip and be a lesson for me to not get duped so easy with Chinese products (even though I knew what I was getting into). Could serve a spare battery for travelling anyway.
Stock on the left, MPJ on the right. Notice the same thickness.
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Stock at bottom, MPJ on top. Same thickness.
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Stock and MPJ.
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The alleged Lumia 820 phone case.
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