Disclaimer: I'm not a designer at all, and I have no design sense whatsoever. HN looks like something I'd design, except there would be no splash of color at the top.
For me, the most striking change in iOS 7 was that the icons lost all of their character. I put together some before and after examples:
The design was... sterilized. I specifically remember that when I updated my iPad and saw the new Safari icon, I said, out loud, "what the fuck is that?"
Again, I don't know anything about usability or- well, I don't even know enough to have the vocabulary to describe what I don't know about design. But I thought the new icons were really dumb.
You're right. The new icons were bad and they're still bad. The Photos and Game Center icons in particular don't communicate anything or make use of any visual metaphors at all. It's like something you'd expect from a second year art major.
More to the point. Why did they need to be changed? What was so wrong with the way they were that a hundred million users needed to re-learn a user interface?
The number one issue that's slowly getting fixed is not knowing which text is clickable or just a label. Then there were slow animations, arguably bad icons and inconsistent font usage. That's what I remember at least, I hope my memory's not failing me.
The most amazing writing on this topic (i.e., how Apple ruined iOS) is by Michael Heilemann, Interface Director at Squarespace. Unfortunately he took down his blog. You can catch pieces of it on web archive though: https://web.archive.org/web/20130724000346/http://binarybons...
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