This article from the New York Times talks about what people use their smartphone for. The top reasons are games and weather. This article is very recent and talks about the most common apps used within 30 days.
Video about media convergence. Some information in the video is from PEW reports, but it contains a lot of other interesting statistics. At the end it mentions someone's hypothesis that what technology is in our smartphones now will fit in a blood cell in 25 years.