SAN FRANCISCO — Apple is throwing out most of the real-world graphical cues from its iPhone and iPad software in what it calls the biggest update since the iPhone's launch in 2007.
The new operating system, called iOS 7, strives for a clean, simple, translucent look. Apple is redesigning all its applications and icons to conform, driven by long-time hardware design chief Jony Ive.
Apple demonstrated the new software at the Worldwide Developers Conference in San Francisco on Monday. The new design direction was widely expected and will show up on iPhones, iPad and iPod Touches this year, the company said.
The overhaul comes at a time when rivals such as Samsung Electronics and Google are trying to get people to defect by developing their own lines of elegant and often less expensive products.
The stiffer competition has slowed Apple's growth in the increasingly important mobile device market, contributing to a 38 percent decline in the company's stock price since the shares peaked at $705.07 in September.
Wall Street didn't seem impressed with Apple's new software approach. Apple's stock dipped $2.92 to close Monday at $438.89.
The redesigned software uses simple graphical elements in neon and pastel colors. Gone is the effort to make the icons look like three-dimensional, embossed objects — a tactic known as "'skeuomorphism," that was favored by Apple's late CEO and co-founder Steve Jobs.
While design modifications could help Apple distinguish its devices from rival phones and tablets, they risk alienating longtime users.
Raluca Budiu, a senior researcher specializing in usability at the Nielsen Norman Group, said the so-called "flat" design can confuse users because it can offer fewer signals about where to tap or click. That's been the case, she said, with Windows 8, which has a very "flat" design. Budiu said it's too early to say if it will be an issue with iOS.
Budiu noted that iOS users seem quite happy with the current iOS, which is easier to use than Google Inc.'s Android, its only big competitor.
Microsoft's radical makeover of the Windows operating system in October was meant to give the company a stronger presence on tablet computers, but it ended up confusing many people who had become accustomed to using the old operating system on traditional desktops and laptops. Research firm IDC blamed Windows 8 for accelerating a decline in PC sales.
Among other changes, Apple's new iOS system will update apps automatically. It will store Web passwords online in Apple's syncing service, iCloud, making them available across devices. The AirDrop feature will allow sharing of big files with Apple-equipped people in the same room.
Apple took a jab at its rival, Samsung Electronics Co., which had been touting its Galaxy phones as better than iPhones because they sport near-field communication chips that allow people to share files by bumping phones together.
"No need to wander around the room bumping your phone with others," said Craig Federighi, senior vice president for software engineering.
The company also stepped up its rivalry with Google, maker of the Android software on Samsung and other phones. Apple said the Siri virtual assistant will use searches from Microsoft's Bing, Google's rival. Apple also is bringing its mapping service to desktops and laptops to compete with Google Maps and others.