Everyone by now knows how important 4G smartphones are to growing 4G subscribers. But it is always good to see how imporant it is by looking at the data. In this LteWorld blog, you can see an important inflection point in subscriber growth. LTE subscribers on NTT DoCoMo's network took one year to reach 1 million, and that was with a large boost from its first LTE smartphone. It then took less than 4 months to reach 2 million LTE subscribers. The inflection point stands out. Note that the month of March is not yet finished, so while it looks like the curve is starting to flatten because the March number is lower than it will be at the end of March, this will not be the case.