Apple’s iOS is the No.1 mobile operating system with 28.6 percent of the smartphone operating system market share in U.S, while Google’s Android with 25.8 percent share stands at No.3, said a report by research firm, The Nielson Company.

However, Android OS is picking up sales, the November data said. According to the report, 40 percent of those who purchased a smartphone in the last six months went for Android, making it the leading OS among recent acquirers. 

On the other hand, RIM’s BlackBerry OS, the No. 2 mobile operating system with 26.1 percent share, is within the margin of error of both Apple iOS and Android.

“In other words, RIM remains statistically tied with both Apple for first and Android for third. Apple’s clear lead over Android notwithstanding, this race might still be too close to call,” said the report.

“All three smartphone OS leaders, Apple iOS, RIM Blackberry and Android are benefitting from strong demand for smartphones. In November, 45 percent of recent acquirers chose a smartphone over a feature phone,” the report added.