Nokia Corp. on Tuesday unveiled its first Lumia smartphone with a metal cover, low-light camera features and new social network apps. Investors expecting a Nokia comeback were not impressed and they sent the company’s stock down more than 5 percent.

The features on the Lumia 925 — slimmer and lighter than the flagship Lumia 920 — will be soon available in the full Lumia Windows 8 range, Nokia said. They include an 8.7 megapixel camera that can take photos in low light conditions and snaps 10 images at once. It enables sharing on various social networks, including Facebook, Twitter, Foursquare, Tumblr, Flickr and Instagram.

The phone is a modified version of earlier Nokia models, said Mikko Ervasti, an analyst at Evli Bank Oyj in Helsinki.

“There is nothing groundbreakingly new or different in the hardware or software design, and there is limited differentiation to Lumia 920 or Lumia 928,” Ervasti said in a note.

Nokia Corp. says the new model will have a price tag of about $610 before subsidies or taxes. It will go on sale next month in China and Europe, and later in the U.S. by T-Mobile.

Earlier Tuesday, Gartner research firm said Nokia’s mobile phone share dropped 4.9 percentage points in the first quarter of 2013, mainly due to a steep decline in feature phone sales. It said its smartphone sales suffered even more, dropping it into 10th place from 8th in the previous quarter.

Chief Executive Officer Stephen Elop is trying to boost a fledgling comeback bid that has so far failed to reverse market- share losses even as Lumia sales are rising. The phone also advances partner Microsoft Corp.’s push into mobile software as the two companies seek to break the dominance of Apple’s iPhone and devices that run Google Inc.’s Android software, led by Samsung Electronics Co. models.

Nokia, which had risen 18 percent in the six days before today’s Lumia 925 introduction, closed down more than 5 percent at 2.79 euros on the Helsinki Stock Exchange.

(Bloomberg News and The Associated Press contributed to this report)