Up to 40 percent of mobile phone users in the United States now own smartphones instead of feature phones with handsets powered by Google\'s Android operating system accounting for 40 percent of the market share, market research company Nielsen said in its latest survey released on Thursday. According to the survey, from May 11 to July 11, this year, 40 percent of mobile device users over 18 in the U.S. own smartphones like iPhone, Android devices and BlackBerry. Google\'s Android platform continued to gain market share, increasing by 1 percent over the last period to 40 percent. Apple\' s iPhone stayed flat with 28 percent while BlakBerry dropped by 1 point to 19 percent of the U.S. smartphone market. Among those potential buyers who said that they are likely to get a new smartphone next year, around one third said that they want to buy an iPhone and one third said an Android device. The survey also asked respondents questions to determine how they embrace the new technologies. Among those \"innovators\" who said that they are usually the first to embrace new technologies, 40 percent of them said that they are looking for an Android phone next year, while 32 percent want the iPhone. The \"late adopters,\" which are about 19 percent of those surveyed, also favor Android over iPhone with 32 percent to 23 percent while 30 percent of them said that they are not sure about their smartphone candidate. The survey noted that those \"undecided\" consumers are the swing vote smartphone makers should be hoping to win over.