Following up on a tip, I did a signal attenuation test on both the Samsung Vibrant (T-Mobile) and Captivate (AT&T).
These are two of Samsung's vaunted Galaxy S smartphones running Android, and are very much top-of-the-line handsets.
As you recall, Steve Jobs made a big deal out of the fact that signal loss is a common problem on many smartphones when the devices are held in a certain way.
Until now, I'd never noticed that problem in any device other than the iPhone 4.
But the Vibrant and Captivate both clearly have "death grip" problems, as well.
Both phones, when held in a tight fist near the bottom of the handset, apparently lost their 3G signal almost immediately.
I say apparently because, while the bars did drop from 5 out of 5 (Captivate) and 3 out of 4 (Vibrant) down to 0 or 1 bar when gripped, those changes did not appear to affect actual signal strength.
I ran the speedtest.net app on both phones while they gripped.
In the Vibrant's case, the phone showed no 3G bars at all, while the Captivate had 1 bar.
While at 1 or 2 bars, the Captivate on AT&T fluctuated between download speeds of 2 megabits per second and 676 kilobits per second. One test dropped as low as 12 kilobits per second, but at that point I had the phone wrapped so tightly in my hands that I couldn't even see the screen.
At 0 bars, the Vibrant on T-Mobile never missed a beat. The slowest download speed was 1.4 megabits per second, up to a max 3.2 megs per second. Again, as I was running these tests, my hands were wrapped so thoroughly around the phone that I could barely see the device.
Web browsing also seemed largely unaffected. The Captivate couldn't load CNN.com when I had every non-screen part of the phone covered with my hands, but did fine in a normal death grip.
The Vibrant, again, connected to CNN.com and ESPN.com just fine regardless of how I held it.
So I guess the bottom line out of these tests is that, yes, these new Samsung phones do appear to suffer moderate to severe signal loss (or at least bar loss) when gripped tightly, especially around the bottom.
But even severe or total bar loss (which requires you to hold the phone in a way that renders the screen all but invisible), doesn't mean your actual connection is degraded. See video of the experiment:
Compare that, for example, to this issue with the iPhone 4:
So I guess I would say that Steve Jobs is probably right when he says that many (if not most) phones can have antenna issues when you cover the phone with your meaty hands.
But I think it's also clear that the iPhone 4 has more severe issues than most devices.
Explore further: Apple 'stunned' to find iPhones show too many bars