Link: https://parakeet.co/blog/the-shape-of-apps/

While icons on iOS (formerly iPhoneOS) have always been rounded squares, and rounded-square icons have existed on Apple platforms for over 20 years now, Mac app icons have historically exhibited a variety of unique silhouettes, which helped identification alongside other visual tools like color, lighting, and dimensionality.

Because app icons from the Mac OS X era are so beloved, it’s very understandable—relatable even—how mandating rounded square app icons is downright heartbreaking to long-time Mac OS X users.

What happened? Why did this happen? And what should we do?

Technology. Pixels and fluff. Things that have existed for decades...

Very interesting article on how apple's icon and style guidelines shaped the look of app icons, I especially liked this part:

The shape of apps is a squircle. And it has been proven to work for everyone. Companies can use their logo as an app icon. Designers can create something specifically for the platform. And both of these get to look like an app. Whether people consider the squircle a container or a canvas, this uniform appearance communicates its function: a squircle represents an app, just like how a piece of paper represents a digital document, or a folder represents, well, a folder.

Semantically, there’s something really beautiful about that. As an icon designer, I appreciate that different types of things have visual distinction.

And I agree! Having different shapes mean different, clear things is quite valuable, especially in MacOS, where having executables all around your home directory is more common.