Quick: Name one thing that stands out about the iPhone 3GS. You can't. It had the same design as the iPhone 3G. It had video. And it had other standard speed bumps. Otherwise, utterly meh.

The iPhone 4S suffers from the same problem as the iPhone 3GS. It's a nice little bump, but there's not much to write home about.

The iPhone 6 could become the best-selling iPhone in history. Unfortunately, it's also the worst design yet. As Joshua Topolsky said in his review for Bloomberg BusinessWeek, "While the iPhone 5S stood out in a crowd of Android smartphones with its chamfered edges and Leica-esque controls, you might not know the iPhone 6 next to the latest Galaxy S5 or the HTC One ... The bold antenna lines that run around the back of the devices and the protruding camera lens make the phones seem slightly less disciplined compared with the company’s previous work." It's just sort of round and pill-shaped. It isn't as striking as previous designs.

The iPhone 5 was a thinner, sleeker version of the iPhone 4. I can't remember who said it, but the black iPhone 5 looks like the iPhone Batman would use if he used an iPhone. (He probably uses some super-slick Batphone from Wayne Enterprises that runs on a forked version of Android.)

However, as good as it looked, it wasn't anywhere near the best-looking or most important design Apple made. The iPhone 5S looks better than the iPhone 5. The black iPhone 5 scratched easily, taking some of the luster off its black design.

The iPhone 3G was miles ahead of its competition when it came out. It was a great phone. And it was such a leap over the original iPhone that it deserves special consideration. However, looking back at the phone, with its curved plastic back, it doesn't leap out as the best-looking iPhone of the bunch.

As Apple's hardware design has evolved through the years, one thing has gone missing: fun. Most of Apple's hardware design is sleek and somewhat cold. The iPhone 5C is none of that. The bright colors of the plastic make you want to pick up the phone. It looks great.

Apple made the slightest tweak to the iPhone 5S, going from black to space gray, and it made all the difference in the world. The chamfered edges gleamed on the iPhone 5S, making the phone pop in a way that the iPhone 5 didn't. The gold iPhone 5S looked great, too.

The original iPhone! Truth be told, it doesn't look all that great. But because of its place in history, it gets special dispensation and bumped toward the top of the list. The first iPhone was a revolution.

OK! So, the iPhone 6 Plus is just a bigger version of the iPhone 6, which I think is one of the worst-looking iPhones ever. The 6 Plus gets no style points. But the big screen is so great and so revolutionary for Apple that it has to be ranked toward the top. I'm still stunned Apple decided to make a big screen. It cuts against the company's ethos of smaller, slimmer, better. It's my favorite iPhone yet.

This is the best-looking iPhone ever. The glass front and glass back are gorgeous. The silver antenna that wrapped around the phone was perfect. It's a museum-worthy piece. In 40 years, this phone will look as good as it looked on the day it was released. It's just an amazing work of art. I used to take the phone out and just stare at it because it looked so good.

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