On the contrary, I think round is a viable choice, if not necessarily the best one. But Apple has already made their choice, so what we're talking about is adding another completely different form factor just to please people who like round watches. Having two differently shaped screens has implications for usability, the operating system, app development, accessories (since they would need another whole line of bands to fit the round screen) and more. So it seems unlikely that they would do this unless they had some very good reasons.
And that is the disconnect that most tech people have with this product. I'm the first to agree that a square is a better shape to convey text. Indeed a true square would make for a more compatible overlay on a round watch than a 4:5 rectangle. That said, what I feel is being discounted by function-over-form traditionalists is fashion. I could be entirely wrong about how Apple will develop this watch, but fashion is the only reason a shoe designer needs to do anything with a shoe. Pleasing people who prefer spiked heels is just as important as how comfortable the shoe is, and in some cases, more important. And I see Apple making great efforts to enter that fickle and often nonsensical business.
As for making two different form factors of the same product, well that doesn't work too well for iPhones and iPads. These are tools that people pick up and use for primarily text based interaction, from reading books, and emails, to typing term papers and grocery lists, as well as watching movies and the like. There's no typing or book reading on a 1" screen, much less movie watching. It's a device which Jony Ive said is intended for "glances" -- anything more involved you should pull out an iPhone.
But the watch is a fashion item. I have friends who have over a dozen different watches, of different shapes and sizes, and styles, to coordinate with different outfits and moods. The watch is the one product Apple makes that encourages people to buy more than one. For those who wear both silver and gold, there's two watch sales right there. 38 stainless & 42 sport for dress and sporting events. Square and round. Two more sales. Unlike the iPad and iPad mini having two different styles of watch will not canibalize sales from each other. People will buy multiple Apple watches to mix it up, just like they do with traditional watches. And having another product with completely different third party accessories is a good thing for everybody, as it means twice the profits.
As I read these forums, I see people discussing the Watch as if it's any other Apple product that you buy one of and upgrade every 1-3 years. But it's not. Ask any watch wearer. They more than likely all own at least two or more. And they won't be identical. Watches make great gifts too, so the parents can buy one for their son's graduation from college and his fiancé can buy him a completely different one for his birthday. And he can buy one for himself, all without duplicating the exact design of the other. And women present a huge expansion market for Apple, who will be the most demanding of this aspect of the watch and its ability to coordinate with their outfits, and looks. It wouldn't do to wear hoop earrings, round belt buckle, round necklace, round buttons, and a square watch.
You and others can discount this opinion all you want. And I may be completely wrong about what Apple intends to do here. But until we see some other behavior pattern from Apple, I don't think it's something that can be easily dismissed, considering what this product represents.
To put it another way, what if the next big wearable was weaving a computer into the threads of clothing, no watch, or phone needed. How will Apple handle this? Would they just make one style of shirt in several sizes and colors, expecting people to wear the same outfit every single day, only changing pants and shoes to mix it up (which Apple offers several complementary styles themselves)? No they would offer many different styles and shapes, from t-shirts to dress shirts, and like the watch bands -- non-tech accessory items to go with them. And this is where I see Apple potentially headed with wearables -- literally getting into the garment business if technology heads that direction, and assuming Apple continues with their current model of designing every aspect about a product. You may not agree, but given their current push into the fashion industry, I don't think we can reject it outright.
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Yes, all squares are rectangles, but not all rectangles are squares. The Apple Watch is rectangular but not square.
While true, rectangular has 11 letters to type, square has 6. Since square conveys the meaning and general appearance of the watch, I chose efficiency over accuracy. With the frame bezel and digital crown, these look very square to me.