Google's popular operating system (OS) Android claimed the largest share with 39 percent of the U.S. consumer smartphone market in the month of June, while Apple's iOS trailed by 11 percent, accounting 28 percent of the entire market, said a new report released by Nielsen.

Market shares of both Android and iOS increased 1 percent each through June, while Research In Motion's (RIM) BlackBerry continued its losing momentum. Source: Nielsen

Market shares of both Android and iOS increased one percent each through June, while Research In Motion's (RIM) BlackBerry continued to lose momentum. For the month of June, it accounted for 20 percent market share, down from 21 percent in May and 23 percent in April.

RIM BlackBerry is followed by smartphones based on Microsoft's Windows Mobile and Windows Phone 7, with nine percent. Next on the list are Palm/HP Web OS and Symbian OS with only two percent market share each.

When it comes to manufacturers, Apple, being the only company manufacturing smartphones with the iOS operating system, continues to the top smartphone maker in the United States with 28 percent share.

The second position has gone to HTC, which accounted for 20 percent market share, which is divided into Android phones (14 percent) and Windows Mobile/Windows Phone 7 devices (six percent).

With 11 percent, Motorola comes at number three, followed by Samsung with 10 percent of the U.S. share. Samsung's Android devices are used by eight percent of smartphone owners, while only two percent of smartphone owners use its Windows Mobile/WP7 phones.

The smartphone market has been dominated by two giants -- Android and iOS. However, a couple of upcoming launches might bring a considerable change to future market shares.

Samsung is set to release its much talked-about Galaxy S2 smartphones through AT&T and Verizon Wireless in the United States sometime in August.

Apple's next generation of iPhone, the iPhone 5, is also on the cards. According to multiple rumors, the feature-rich iPhone 5 will be launched in September or October.