I know most of you have a 5, but if anyone is looking for a 4S battery case, here is my review of the Tekkeon.
I purchased this case for $50 at Microcenter.
The best thing about this case is the form factor. Because of the tampered edges, it still feels really slim in the hand like the 3GS, or the new HTC 8X.
It is also quite light at 1.84 oz. This is less than the mophie, which weighs 2.5 oz.
How did they get it to be so slim and light? It's because its battery is only 1200mah. However, Tekkon claims that the additional battery directly powers the iPhone, and because of that the case can get up to 90% efficiency.
Is this true? It sure seems to be.
I unplugged my iPhone 24 hours ago, and after using up the battery case, this is where I'm at.
With 58% of battery left on my iPhone, I should be good to go for at least another 4 hours of usage.
Mic/speaker phone: The speaker seems louder. As for the mic, I had about an hour of phone calls throughout the day, and not one person complained about echoing.
The case comes in red, white or black. Additional battery modules can also be purchased for $20. This seems like a really easy way to get even more battery power. I have emailed customer service for a local pickup, but they haven't replied to me after 2 days. Looking at their website, it seems that the support isn't the best. I will edit this section if I get a reply from them. Got a reply today. Great customer service! They were probably closed because of the new year, so I was the impatient one. 
The official page for the case is http://www.tekkeon.com/products-mypower-iphone-1280.html
Conclusion: Highly recommended
I purchased this case for $50 at Microcenter.
The best thing about this case is the form factor. Because of the tampered edges, it still feels really slim in the hand like the 3GS, or the new HTC 8X.
It is also quite light at 1.84 oz. This is less than the mophie, which weighs 2.5 oz.
How did they get it to be so slim and light? It's because its battery is only 1200mah. However, Tekkon claims that the additional battery directly powers the iPhone, and because of that the case can get up to 90% efficiency.
Is this true? It sure seems to be.
I unplugged my iPhone 24 hours ago, and after using up the battery case, this is where I'm at.
With 58% of battery left on my iPhone, I should be good to go for at least another 4 hours of usage.
Mic/speaker phone: The speaker seems louder. As for the mic, I had about an hour of phone calls throughout the day, and not one person complained about echoing.
The case comes in red, white or black. Additional battery modules can also be purchased for $20. This seems like a really easy way to get even more battery power.
The official page for the case is http://www.tekkeon.com/products-mypower-iphone-1280.html
Conclusion: Highly recommended
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