When iOS7 first was announced a lot was said about the minimalist design. Many put forth how it is a step backward and others downright hated it. Since it's release I have been using it heavily on both an iPad mini and an iPad and I've come to realize the design of iOS7 is sheer genius.
My appreciation of the simpler design of iOS7 didn't happen right away. It's grown the more I use it and especially the more I use other platforms and come back to iOS7.
I've always liked efficient UI designs but never felt as strongly about them until now. It took me a while to figure out why I find iOS7 to be so good to use, and it surprised me when it hit me what makes it so good.
The clean design of iOS7 gets out of my way when I'm using it. Completely. No matter which iOS7 app I use, the interface doesn't interfere with the information I've requested. It doesn't matter if I'm using Calendar, Notes, Safari, or any other iOS7 app, it's as if the interface pulls way back and focusses my attention on the information on display. That's significant because in every case, that's the information I want.
The simple interface displayed on a crisp, white background is attractive, but it also prevents the UI from overwhelming the importance of the data requested. Whether I ask for a web page, calendar, note, or reminder, it is presented front and center without distraction.
Not everyone will agree with that but that's the way I see it the more I use it. This is an effective UI design as a result.
Note that I am referring to the app interface design and not the home screen icons. Those are OK but icons are icons. How they look doesn't affect how enjoyable using a device might be for me. But app interface is one of the most important features an OS provides, and Sir Jony Ive hit a homerun with iOS7.