Smartphones are exploding among the United States population, with nearly 50 percent of everyone in the country now owning one, appolicious reports. And there are rising trends even among teenagers. According to analyst Piper Jaffray analyst Gene Munster, a survey of 5,600 U.S. teens found that about 34 percent of them had iPhones. What’s more, Munster reported that another 60 percent of those interviewed said they intend to grab an iPhone in the near future, according to a story from Macrumors [1]. Of course, surveys like this are far from exact. Telling a survey taker your “intentions” isn’t always accurate, because there are a lot of factors to making a purchasing decision, including price, location and other such inconveniences. Still, it suggests the iPhone remains extremely popular among young people, and that should be very good news for Apple and its marketing teams that are apparently aiming at a younger, lower-spending end of the spectrum…