Consumer Reports tested three iPhone 4s and found problems with signal degradation when the hand touches a spot in the phone's lower left side. Duct tape solves the problem though.
"The signal problem is the reason that we did not cite the iPhone 4 as a "recommended" model, even though its score in our other tests placed it atop the latest Ratings of smart phones that were released today.
"The iPhone scored high, in part because it sports the sharpest display and best video camera we've seen on any phone, and even outshines its high-scoring predecessors with improved battery life and such new features as a front-facing camera for video chats and a built-in gyroscope that turns the phone into a super-responsive game controller. But Apple needs to come up with a permanent—and free—fix for the antenna problem before we can recommend the iPhone 4."
It recommends the 3GS instead because of antenna issue on the iPhone 4.
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