Google and Microsoft have introduced new champions in the fiercely competitive smartphone arena a week ahead of what is likely to be the hotly-anticipated debut of a next-generation iPhone by Apple.

Microsoft and Nokia joined Wednesday to boost their smartphone arsenal with two new Lumia handsets powered by Windows 8 software.

The Nokia Lumia 820 and 920 are part of the Finnish-based company's strategy of offering "an alternative to the faceless black and grey monoblocs that you see out there," said Nokia president and chief executive Stephen Elop at a New York launch event.

"This is Lumia, the world's most innovative smartphone," Elop said in unveiling the two new devices.

Microsoft chief executive Steve Ballmer also appeared at the event, which offered no specifics on launch dates or prices in various markets.

Later in the day, Motorola Mobility added three powerful Android smartphones to its Droid family in a separate event in New York City.

The additions of RAZR M, RAZR HD, and RAZR MAXX HD to the Motorola line-up came as the first major product news from the company since it was bought by Internet giant Google a year ago in a $12.5 billion deal.

The RAZR smartphones are powered by Google's Android software and synched to the US telecom network of Verizon Wireless.

The media events in Manhattan shined early spotlights on Microsoft and Android mobile gadget platforms that compete with Apple iOS and drew attention to handsets that will compete with iPhones for holiday shoppers' cash.

Apple shares closed the Nasdaq trading day down nearly five dollars to $670.23 but gained back a few cents after-hours.

"(Microsoft and Google) platforms are really out-innovating Apple but that might not matter to consumers," said Gartner Research vice president of mobile computing Ken Delaney.

"The consumer goes into a store with a heavy bias to buy an Apple product and you have to do a lot to unseat them from that love affair."

Delaney predicted that if Apple debuts an iPhone 5 as expected in San Francisco on September 12, it will be a "monster event" that sets the stage for blockbuster sales.

Apple this week sent email invitations with the cryptic message, "It's almost here," and a large number "12" casting a shadow that appeared to be the number five, suggesting that the event would spotlight the long-anticipated iPhone 5.

Leaks and rumors portray the new iPhone as having a larger touch-screen than its predecessor and say that it will be available by the end of the month.

Demand for what is being referred to as "iPhone 5" is likely to be hot, with analysts convinced that many people in the market for handsets have put off purchases to wait for the latest offering from Apple.

"While our checks indicated consumers are delaying iPhone 4S purchases in anticipation of the iPhone 5, we anticipate an LTE iPhone 5 with a new hardware form factor will result in record iPhone sales," Canaccord Genuity brokerage firm said in a note to investors.

Piper Jaffray analyst Gene Munster has gone on record predicting that Apple could sell as many as 10 million iPhone 5 handsets the week of its release.

Smartphones powered by Google's Android software continued to dominate with 52.2 percent of the US market, but Apple's iOS was the second most popular smartphone platform with 33.4 percent, according to comScore.

Nokia, once the leader in mobile phones, has been losing market share as consumers move to smartphones powered by Apple's iOS or Google's Android operating system.

The Finnish company's new strategy is phasing out its Symbian smartphones in favor of a partnership with Microsoft.

"This is all about the comeback for Windows Phone and for Nokia," Delaney said after attending the New York event held by the companies.

"I think they have a shot here," he continued. "They could take some share from Android and some from Apple."

Nokia created "great hardware" for the Lumia line and loaded it with software that "out-distances it in a number of areas from Google and Apple," according to the analyst.

Investors were disappointed by the lack of specifics regarding when the new Lumia smartphones will be available.

Nokia shares took a blow, sinking nearly 15 percent on the New York Stock Exchange to close at $2.38 but rose five cents in after-hours trades.

"Nokia's a shadow of its old self and success of the new Lumia devices is critical," RBC Capital Markets said in a note to investors.

Google shares were down less than a percent for the day, trading at $680.40 after hours on the Nasdaq.