Worldwide sales of mobile phones to end users reached 419 million units in the second quarter of 2012, a 2.3 percent decline from the second quarter of 2011, according to Gartner.

Smartphone sales accounted for 36.7 percent of total mobile phone sales and grew 42.7 percent in the second quarter of 2012, the research firm found.

"Demand slowed further in the second quarter of 2012," said Anshul Gupta, principal research analyst at Gartner. "The challenging economic environment and users postponing upgrades to take advantage of high-profile device launches and promotions available later in the year slowed demand across markets. Demand of feature phones continued to decline, significantly weakening the overall mobile phone market.

"High-profile smartphone launches from key manufacturers such as the anticipated Apple iPhone 5, along with Chinese manufacturers pushing 3G and preparing for major device launches in the second half of 2012, will drive the smartphone market upward. However, feature phones will continue to see pressure," Mr. Gupta said.

In the second quarter of 2012, Samsung's mobile phone sales remained very strong - up 29.5 percent from the second quarter of 2011, and managed to extend its lead over both Apple and Nokia quarter on quarter. This quarter's growth was driven by record sales of Galaxy smartphones, meaning smartphones now account for 50.4 percent of all Samsung mobile devices, or 45.6 million units. Demand for the new Galaxy S3 was particularly strong, exceeding Samsung's own expectations, with a reported 10 million units reached in the two months after its release. The Galaxy S3 was the best-selling Android product in the quarter and could have been higher but for product shortages.

In the second quarter of 2012, consumer demand for the Apple iPhone weakened as sales fell 12.6 percent from the first quarter of 2012, but grew 47.4 percent year on year. Depending on the exact launch date of the new iPhone, Apple might experience another weaker-than-usual quarter in the third quarter of 2012, while Apple will be ready to take advantage of the strong holiday sales in North America and Western Europe that have historically remained immune to economic pressure.

"Samsung and Apple continued to dominate the smartphone market, together taking about half the market share, and widening the gap to other manufacturers. No other smartphone vendors had share close to 10 percent," Mr. Anshul said. "In the race to be top smartphone manufacturer in 2012, Samsung has consistently increased its lead over Apple, and its open OS market share increased to one-and-a-half times that of Apple in the second quarter of 2012."

Nokia's mobile phone sales declined 14.8 percent in the second quarter of 2012. Nokia is battling fiercely with white-box and new emerging device manufacturers to defend its feature phones sales. Nokia succeeded, to a certain extent, in winning feature phone market share as its sales grew quarter-on-quarter. While posting sequential growth in the feature phone market, Nokia's Lumia devices continue to struggle to find a place in consumers' minds as a replacement for Android.

"Declining smartphone sales is worsening Nokia's overall position, as it had already lost the No. 1 position to Samsung in the previous quarter and is facing reduced profitability due to continuous declining sales of premium smartphones," said Mr. Gupta.

In the smartphone OS market, Android extended its lead with an increase of 20.7 percentage points in market share in the second quarter of 2012. While Apple's iOS market share slightly grew year over year (0.6 percent), it declined 3.7 percentage points quarter on quarter, as users postponed their upgrade decisions in most markets ahead of the upcoming launch of the iPhone 5.

Gartner analysts said the arrival of the iPhone 5 should provide the greatest upgrade opportunity yet as the expected new design with a larger screen and likely other stylistic changes to the form factor will certainly make a strong case for iPhone 4 users to upgrade.