The iPhone 4 has a unique design feature—it uses the stainless steel frame and bezel to serve as radio antennas instead of hiding them inside the case. Steve Jobs made a big deal of the design during his WWDC keynote earlier this month, while iFixit described the design as "a work of genius." Despite the crafty design, it turns out that some users are experiencing a problem where holding the phone a certain way in the left hand can significantly reduce 3G signal strength. Scattered reports of the problem began appearing Wednesday as new iPhones were delivered early to many who preordered on June 15. Insanely Great Mac was able to reliably reproduce the problem, narrowing the cause to touching the iPhone 4's bezel on the bottom left corner. Essentially, gripping the iPhone in the left hand just right can cause the palm to bridge the left and bottom antenna sections of the bezel, cutting reception quality. In the case of Insanely Great Mac, this caused calls to be dropped. Developer Matt Legend Gemmell did some testing of his own and confirmed that touching the area on the bottom left would reliably and sharply cut 3G signal strength. However, he found that EDGE and WiFi reception were not affected by the problem. And in his case, calls were not dropped. We tried to replicate the problem with our own iPhone 4 models, fresh from the Apple Store this morning. At first we didn't notice any issues with signal strength. After some effort (and help from a video so that we could perfect our technique) we were able to reproduce the problem—if your palms aren't sweaty, we discovered it actually helps to lick them. It's unfortunate that Apple appears to have overlooked such an important detail—after all, attention to detail is something that Apple generally prides itself on. Given the methods that Apple used to attempt to keep iPhone 4 prototypes under wraps, though, it's possible that wireless engineers may not have caught this issue during testing. Since those carrying prototypes had them disguised in a plastic case made to resemble an iPhone 3GS, the antenna bridging problem could have been mitigated by plastic covering the bezel. It's also possible that those doing the testing never held the phone in the specific way necessary to trigger the problem. Those of us on staff found that our natural grips didn't automatically cause this issue, but cupping the iPhone 4 tightly in the palm would. If you are left-handed or predominantly use the phone in your left hand, you may want to be aware of the problem. The known workarounds for now include holding the phone without cupping it, holding it higher up on the bezel, holding it in your right hand, or using a protective case. We certainly hope that Apple didn't design its iPhone 4 Bumpers just to mitigate this problem.