Finnish mobile phone maker Nokia has finally launched two new smartphones based on Microsoft's new Windows Phone 7.5 operating system.

The Lumia 800 and the Lumia 710 mark are the beginning of Nokia's fightback against Apple's iPhone and rivals using Google's Android software, BBC reports.

Now Microsoft's new Windows Phone 7.5 operating system will power all Nokia's smartphones. Nokia's boss, Stephen Elop said the launch marked the "rebirth" of Nokia.

The Lumia 800 has a durable polycarbonate plastic body with 3.7-inch (480x800 pixels) touch screen. It's powered by a 1.4GHz Qualcomm MSM8255 processor and has 16GB of internal memory (up to 25GB). It comes with an 8-megapixel camera. The camera app offers various editing options, such as red-eye reduction,and white balance controls. Pricing is expected to go around 420 Euros ($585 U.S.) The Lumia 800 will hit the market immediately in France, Germany, Italy, UK, Spain and the Netherlands in November, according to CNET.

Smartphone includes services such ESPN Sports Hub, Nokia Drive for free, turn-by-turn voice-guided navigation, and Nokia Music and Mix Radio, Nokia Pulse which combines elements of social networking with location services.

The Lumia 710 is a cheaper alternative to the 800 model. Priced at 270 Euros ($376) it has the same 1.4GHz processor and 3.7-inch ClearBack AMOLED touch screen. It has 8GB of internal memory (up to 16B cards) and comes with a 5-megapixel camera. It will be available in black or white but offers the option of customizing it with replaceable back covers. The Lumia 710 is expected to ship in Russia, Taiwan, India, Hong Kong, and Singapore later this year, with more markets coming in the first half of 2012.

The firm also announced four new basic phones. The new range will be called Asha, a name that clearly identifies Nokia's target market: the name is derived from the Hindi word for "hope". Although the phones will be relatively cheap, they will sport features like touch screens, 5 mega pixel cameras, bright screens, 32GB storage for music and long battery life. Nokia's main focus will be on its new smartphones.

Nokia Corp. announced a third-quarter net loss of €68 million ($94 million) from a profit of €529 million a year earlier as sales of smartphones plunged 39 percent and overall revenue dipped 13 percent. Net sales in July through September were €8.9 billion, down from €10.2 billion in the same period in 2010.

The Finnish cellphone maker said the decrease in device and services sales was driven by a lower average selling price in mobile handsets and smartphones and an appreciation of the euro against certain currencies.

It said the lower volumes were due to the "strong momentum of competing smartphone platforms" relative to Nokia's higher priced Symbian devices, as well as "pricing tactics by certain competitors."