It looks like the iPhone 4 is a hit so long as users don’t touch the bottom left-hand corner of the phone. According to multiple reports online and confirmed by informal tests at Wireless Week, Apple’s new smartphone loses 3G, Wi-Fi and Bluetooth connectivity when the bottom left-hand portion of the phone’s steel-band antenna makes contact with the skin.

The iPhone 4 features an unorthodox antenna that wraps around the outside of the phone in the form of a stainless steel band. While some say the new antenna does improve connectivity, that’s apparently not true when held in the left hand, where the palm cups that particular part of the phone’s antenna. The problem can be remedied by the use of one of Apple’s “rubber bumpers,” essentially a piece of rubber that wraps around the outside of the phone.

Apple was unavailable for comment before press time.

The iPhone 4 has been plagued with supply problems as pre-orders far exceeded projected demand. Today marks the device’s official launch, although some who placed pre-orders began receiving their phone two days ago.

Kevin Burden, vice president and research practice director of mobile devices for ABI Research, says he’s not surprised that there would be glitches with a new technology.

“This antenna that they put into the iPhone 4 is a completely new design. You have to assume that there’s going to be some bugs that have to be worked out,” Burden says.

Burden says that Apple’s antenna problems have been there from the very beginning. In his discussion with RF engineers, Burden has found that popular opinion was that the original iPhone had problems because of its curves.

“They chose style over performance,” he says, explaining that an antenna wants to reverberate outwards towards the horizon, but the original iPhone’s curves actually sent the signal straight into the ground. The new iPhone’s hard-edged curves are about sending that signal outward, he says.

Given the space constraints in new devices, there are going to be compromises with any approach, he says.  

For now, it looks like adding one of Apple’s rubber bumpers, or at least a protective case of some kind, will be the compromise that iPhone 4 users will have to live with, especially if they’re left-handed.