According to the new data gathered by Nielsen just this July 2011, forty percent of the mobile users in the United States now own smartphones. Furthermore, forty percent of these smartphones are reported to run the Android operating system.

Nielsen data shows Android to be the most widely-used operating system in the United States. Other known operating systems (OS) are Apple’s iOS with 28%, which comes second to Android; RIM Blackberry with 19%; Windows Phone with 7.1%; and other OSes composes the remaining 5% of the pie.

In the U.S., more than half of mobile users use feature phones for a number of reasons. One is that these feature phones are cheaper in comparison to smartphones. In addition to this, users are still in doubt of whether a smartphone is worth it.

Smartphones offer new revenue streams for basic features like data, messaging, and others. Manufacturers and carriers strongly promote their smartphone products. This has contributed a lot to the increase in number of smartphone users.

When asked whether the users would buy new smartphones in the next year, about one-third of them opted for smartphones with Apple’s iOS. Also one-third of the users wanted their new smartphones to run Android.

Among the so-called “Innovators”, “Early Adopters” and “Late Adopters”, or those who are usually the first ones to embrace the new technologies, Android is still considered the “Next Desired Operating System.”

Compared to iOS (32%), forty percent of the Innovators chose Android, according to the research done by Nielsen.

Apple’s iOS (38%) slightly advanced by 1% from Android when Early Adopters were asked. All the other operating systems lagged behind Android and iOS.

However, looking at the distribution, Android is still considered to be the next desired operating system in smartphones. Looking at these facts, which OS are you picking outfor your next smartphone – Android or iOS?