iPhone 3G weird swirl screen defect

Did any sort of weird substance drip on it -- like a strong chemical? Also, does the touch screen still work fine in that area?

That's called [Newton's Rings|http://en.wikipedia.org/wiki/Newton's_rings]. That phenomenon occurs when there is an air gap between two surfaces (one of which is translucent). In this case, it's likely that the gap between your [LCD and the clear glass over the front bezel|http://www.ifixit.com/Guide/First-Look/iPhone3G/images/oEHBJQC3PWMANSKt-l arge.jpg] is such that they are almost touching at that point, but not quite.

There's not much you can do since there's always some manufacturing variation in these things. Having said that it can be considered a factory defect. Take it back to the Apple store and ask for a different one.

Wow... great explanation! Nice to see this kind of post!

I have the same thing on my 3g iPhone. Bought 2 identical 8GB iPhones in September of 2008 and mine has this happening about an inch long right in the center of the screen directly above the button on the bottom.

My wife's phone does not have any blemishes at all.

I have an appointment tomorrow with the Genius bar. Wish me luck.

Well, good news.

My iPhone 3g was swapped out for another one. But not until the "genius" tried to tell me that "all" iphones have the same problem. He even tried showing me his iphone claiming that it had the same problem. I could not see anything. I mentioned again, that my wife's phone has no problems, and the phones on display in the store (which are handled all day long) are perfect. (albeit a little filthy...dirty..etc.)

Anyway, phone replaced. Problem solved.

Unfortunately, you have to put up with some "condescending" idiots in the "genius bar" to get it done.

When I first got my iPhone 3G, there was this problem. I walked out of the store and noticed it immediately so they replaced it right away. A few weeks ago I noticed on my replacement, there was one in the same spot! Since I love my iPhone more than my own parents (ok, not quite) I take very good care of it, and knew that I had not physically damaged it. When I went up to the store today, they asked me, in kind of an accusing way, had I dropped it in water, or taken a shower with it. I told them no and they told me that they'll replace it, but if it ever happens again I'll need to figure out what the problem is. Anyway, I'm taking it back up to the store right now and bringing a copy of this thread with me.

I know I'm not the OP, but thanks for answering a question I had as well.