Apple now has more than a quarter of the US smartphone market, according to the latest figures from ComScore.
Its share inched up by 1.2 percentage points during the fourth quarter last year to 25.3 percent, making it the number two supplier.
In first place was RIM, with 41.6 percent of the market, a one percentage point decline from the previous quarter. Microsoft's share with Windows Mobile fell by the same amount, to 18 percent, giving it third place.
Palm's share slid sharply during the quarter, from 8.3 percent to 6.1 percent. Google's Android platform, though, did very well, rising from 2.5 percent of the market in September to 5.2 percent.
Motorola was the top mobile handset maker overall, with 23.5 percent market share, followed by Samsung with 21.2 percent and Nokia with 9.2 percent.
In total, says ComScore, there were 234 million people aged over 13 using a mobile device. Nearly two-thirds of them now use text messaging, compared with 59 percent in the previous quarter. Browsers were used by 27.5 percent, and 21.6 percent played games.