CNN's John D. Sutter is attending the Apple announcement and is posting updates to the CNN Tech feed on Twitter, @cnntech.
San Francisco, California (CNN) -- Apple CEO Steve Jobs on Monday introduced the newest version of the company's popular smartphone: iPhone 4.
"We think it's the biggest leap we've taken since the original iPhone," Jobs told an enthusiastic audience at the company's annual developers conference. "We're really proud of it."
The phone will come in two colors -- black and white -- and will go on sale June 24 in the United States and four other countries. It will cost $199 for 16GB of storage and $299 for 32GB.
Jobs said iPhone 4 will be "the thinnest smartphone on the planet" at 9.3 mm thick -- 24 percent thinner than the iPhone 3GS, the company's current model. It's been designed with a glass back and metal around the sides.
The device will have a front-facing camera for video conferencing, and the camera on the back will have an LED flash, Jobs said. The phone will have a 5 megapixel camera with a backside illuminated sensor, which he said is fairly new to smartphones. It also will have a 5X digital zoom.
Jobs drew perhaps his wildest cheers when he used the new phone to conduct a video chat with an Apple staffer using a feature he called FaceTime. The feature will work seamlessly between iPhone 4s anywhere there is a Wi-Fi connection, he said.
"This is our new baby," he said of the phone. "I hope you love it as much as we do."
Spotty Wi-Fi coverage inside the Moscone Center interrupted Jobs' presentation several times. At one point he asked the audience to turn off their Wi-Fi base stations or he wouldn't keep showing demos of the new phone.
Jobs referenced the phone's new operating system -- announced in April -- which he called "iOS" and which will allow multitasking -- letting users surf the Web on their phones, for example, while listening to streaming radio through Pandora. It's "the most advanced mobile operating system in the world," he said.
The iOS 4 will be released for free on June 21. Owners of the iPhone 3GS will be able to update their phones with the new software, although it will not work on older iPhone models.
The new iOS adds Bing to the search choices, although Google will still be the default and Yahoo is an option, too.
Jobs also announced an iMovie app for the iPhone that would allow users to shoot, edit and share movies from the "device you carry in your pocket everyday." The iMovie app will cost $4.99.
Jobs announced to wild cheers from the audience that iPhone 4 will have a gyroscope, which measures motion on six axes and is sensitive to gravity. The gyroscope will be good for gaming, he said.
The new phone will also have better battery life, including seven hours of talk time on 3G -- about two hours more than the iPhone 3GS -- and 10 hours of web browsing on Wi-Fi.
Despite the massive hype that greets every iPhone announcement, the BlackBerry, made by Research In Motion, is still the top-selling smartphone on the market. It is geared toward business clients and doesn't have all of the features that touch-screen phones do.
Nevertheless, Jobs cited some statistics that show the iPhone commands 58.2 percent of mobile browser usage in the U.S. -- 2.5 times as much as Android's 22.7 percent.
"This may help you put things in perspective," he said, to some laughs. More than 5 billion apps have been downloaded from Apple's App Store, Jobs said. He also drew cheers when he said that 70 percent of app sales goes to developers -- a total of $1 billion to date.
The new iPhone comes as Apple faces increasing competition from other smartphone makers. In many ways, the company has set the standard for what Internet- and app-enabled phones are capable of. But the Motorola Droid, Google Nexus One and Palm Pre all have proved to be decent competitors to the Apple iPhone in recent months.
In the first few months of 2010, phones running Google's Android operating system were more popular with consumers than those from Apple, according to CNET.
The iPhone probably won't be the only topic of discussion at WWDC.
Jobs in his keynote also announced three new iPhone entertainment apps:
Karthik Bala, senior vice president at Activision, announced a new "Guitar Hero" app for the iPhone and iPod Touch, on sale today for $2.99.
Mark Pincus, Zynga's CEO, announced that FarmVille, the company's wildly popular Facebook game, will have an iPhone app by the end of June.
Jobs introduced Netflix CEO Reed Hastings, who said Netflix is launching a free app for the iPhone, which will be available this summer and will let users download and watch movies on the go.
Jobs described the Apple App Store as "the most vibrant app community on the planet," with more than 225,000 apps available. He also defended Apple's mysterious app-approval process, saying that 15,000 apps are submitted to Apple each week and 95 percent of those are approved within seven days.
Jobs praised HTML5, which some believe will be the next standard for computer language. "HTML5 is a fully open, uncontrolled platform that is forged and defined by widely respected standards bodies," he said.
Jobs began his remarks by praising the success of his company's iPad tablet computer.
According to Jobs, Apple has sold more than 2 million iPads since the device went on sale two months ago. The iPad will be in 19 countries by the end of July, he said. More than 35 million iPad apps have been downloaded, or 17 apps per iPad sold.
The iPad also appears to be catching on as an electronic reading device. In 65 days, iPad users have downloaded 5 million books -- about 2.5 books per iPad, Jobs said.
Wearing his usual black turtleneck and jeans, Jobs took the stage to a standing ovation from the audience and a shout of, "We love you Steve!"
The WWDC is hosting some 5,200 attendees from 57 countries, Jobs said.