Apple has unveiled a brighter look for the user interface of its smart device iOS operating system - the first to be overseen by its design chief Jony Ive.
He said the aim was to make the system look "cleaner" to help "elevate" users' content.
It involves a shift away from skeuomorphism - the use of leather, wood and other real-world inspired textures and artifacts in apps.
A similar change has also been made to the OS X system for Mac computers.
Highlighting the new look of the firm's Game Center app, Apple's senior vice president of Software Engineering Craig Federighi joked: "We just completely ran out of green felt and wood - this has got to be good for the environment."
He also showed off a parallax effect which means icons shift against the background image as an iPhone-user tilts their handset one way and another, based on feedback from the device's accelerometer sensor.
"The new version is almost unrecognizable, which will make it polarising," said Jan Dawson, chief telecoms analyst at the consultancy Ovum.
"Some people will love that their phone feels new and different, while others will be disoriented by the newness.
"Finding your Settings app is hard when the icon has totally changed, and the many people who easily get disoriented by their gadgets may well have a negative experience.
"On the other hand, this is a clear statement from Apple that it acknowledges the need to refresh the user interface and is willing to do something pretty dramatic.
Other new features in iOS 7 include:
- Automatic app updates
- A swipe-up Control Center feature which brings together frequently used functions such as turning on wi-fi or bluetooth, adjusting the volume, and using the iPhone as a torch
- The ability to carry out searches via Microsoft's Bing service within the voice-controlled Siri app, which also features new voices
- An anti-theft measure which requires a user to enter an associated ID and password before being able to deactivate a device's Find My iPhone feature
- Redesigned fonts to create the appearance of sharper text
About 37.4 million iPhones shipped worldwide in the January-to-March quarter according to market intelligence firm IDC, confirming its status as Apple's biggest source of revenue.
Apple's products might still be more profitable, but IDC suggested it needed the refresh.Although that was a rise on the same period in 2012, the study suggests the firm's smartphone market share slipped to 17.3% while Android's grew to 75%, thanks in large part to Samsung's success. It also indicates Apple is facing a similar trend in the tablet sector.
"People were getting a bit bored with the old design so Apple needed to make significant changes," said IDC's mobile device research director Francisco Jeronimo.
Apple said iOS 7 would be released to the public in the autumn.
