It's a common and very relevant pushback for wireless health: Not everyone has a smartphone. While there are plenty of solutions that do not require a smartphone, clearly health management tools are far richer when a smartphone platform is in play. RBC analyst Mike Abramsky estimates that by the end of 2011 -- just two years from now -- worldwide smartphone sales will pass worldwide PC sales. The two figures intersect when PCs and smartphones are both shipping about 400 million units each year. Business Insider put together a chart that tracks this trend:

For more from Business Insider, read their brief article here.