The big talking point of iOS 7 is its all-new user interface, led by Apple's head of industrial design, Sir Jony Ive. The iPhone and iPad operating system has ditched the real-world metaphors like torn yellow paper in the Notes app, in favour of a much simpler style

Home Screen
Some of the biggest changes are found on the home screen, where every

iSO7 Home Screen

Although flat in terms of colour and texture, iOS 7 is a user interface of many layers. At the back you have the wallpaper, then the home screen icons, followed by the Notification Center and Control Center, before finally pop-up notifications and alerts sitting at the top. Covering the home screen, Notification and Control centres are semi-transparent. Folders have also been simplified by removing the grey fabric background in favour of the same blurred, semi-transparent effect similar to that of a bathroom window, allowing the general colour of your wallpaper to shine through, but no detail. 


Multitasking

As before, Multitasking is found with a double-press of the Home button, but now the familiar list of open apps is joined by a thumbnail screenshot showing the state it's currently in. Removing these apps from the Multitasking bar - and thus forcing them to close - is now done by swiping the thumbnails up and off the screen; a long press of the app icon is no longer required.

Calendar, Settings, Clock, Notes, Music, Newsstand and Phone

iOS7 Settings

All of these applications share a similar white and transparent design.Applications are no longer topped with a blue bar and icons within apps have all been simplified - in Settings, for example, every icon is now the same shade of blue and there is less shadowing around the on/off toggle switches for Wi-Fi and Bluetooth.

Messages
The iOS messaging app also gets the white treatment, replacing the light blue background of all previous builds of iOS, and this time the highlight colour is blue instead of orange. Sent and received messages still show up in green and silver bubbles, but they no longer have a shine to them as they did before

Camera
Often criticised for being too basic and offing few of the features available in Windows Phone 8 and Android, the iOS 7 camera app is all-new but still offers few features. Swipe left or right to quickly switch between video, photo, panorama and a new square photo-taking tool, and there are now a number of filters to apply to photos as you take them. It's still basic, and you won't see complex aperture, white balance and metering customisation, but it's a step in the right direction.
There are many more changes in iOS 7.


Source: Internet.