Apple's bumper has caused a lot of commotion across the Internet. Some suspect that Apple knew of its antenna issue and that's why they developed the case, while others scoff at the absurdly high MSRP. No matter what your thoughts on the bumper case are, Neowin has learned that the case actually improves the antenna performance on the iPhone 4.
The picture above shows the iPhone without the bumper case (left) and with the bumper case (right), for reference, compare the "Tot. Rad. Pwr." and larger numbers are better.
The right side of the picture shows 28 dBm across all three benchmarks which outperforms the naked iPhone. While not a significant increase, it does show a minor improvement when compared to the naked iPhone.
The bumper case improving reception comes in stark contrast to the Vapor 4 case that reduced the iPhones antenna performance by 99%. What can be learned from this case testing is that attaching a case to your device can drastically affect how your cell phone will perform for better and for worse.
A special thanks to our friends at ETS Lindgren for helping us out with testing of various devices in their anechoic chambers.