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Many of the icons' colors are muted. Muted colors are faux retro and faux vintage, both of which are typical of hipsters' tastes.

You need turn the brightness up from minimum or go get an eye test if you think the colours are muted on ios7!
 
On what planet are these colors "muted?" I'm colorblind and even I can tell they're bright:

Image

The app icons using muted colors are:

1. Photos
2. Camera
3. Weather
4. Maps
5. Notes
6. Reminders
7. Game Center
8. Newsstand
9. Passbook
10. Settings
11. Mail
12. Safari

Not every color in those app icons are muted (eg. the white color is not muted), but most colors in those app icons are muted.
 
That's the current trend thus that is who designers are gonna based their current designs.

Trends go full circle, you might get a 20's style icons in iOS 10
 
IFilters have got to be the worst thing ever to happen to digital photography. Instead of seeing the most genuine reproduction of a real-life image that the iPhone's camera is capable of producing, millions of people will now destroy their photos' data by adding a faux vintage filter to their picture.

I don't know if hipsters are to blame, but I agree with you on this one.
 
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