eMarketer bases all of its forecasts on a multipronged approach that focuses on both worldwide and local trends in the economy, technology and population, along with company-, product-, country- and demographic-specific trends, and trends in specific consumer behaviors. We analyze quantitative and qualitative data from a variety of research firms, government agencies, media outlets and company reports, weighting each piece of information based on methodology and soundness. - See more at: http://www.emarketer.com/Article/2-Billion-Consumers-Worldwide-Smartphones-by-2016/1011694#sthash.NlGbvjz5.dpuf