krou (1027572) writes "A number of users are reporting signal problems with their iPhone 4, complaining that there's 'a drop in signal strength when the phone is held'. Richard Warner wrote to the BBC saying the phone was "useless in its current state": Apple have created a phone that has an antenna on the bottom left-hand side of the phone. This means that when you hold it in your left hand, the signal bars slowly fade until there is no signal." Some users have also been complaining on YouTube, with one user complaining "it won't even run the [upload] test when I am holding the phone... once I let go, it makes a connection and runs the test. Hold it a second time, and the upload test will not start." There is speculation that the issue comes 'from the way the integrated antenna is constructed. One section provides mobile reception, while another is for wi-fi' and that 'touching the bottom of the phone bridges this gap, affecting signal strength.'"
Link to Original Source