The Apple TV is an iOS device, and is certainly lagging behind other iOS devices in terms of sales. But according to a report on RapidTVNews, Apple is on track to sell 4 mlllion Apple TV settop boxes in 2011, representing one-third of global sales of an expected 12 million. The report says that the market for connected settop boxes has doubled this year, and it seems that the trend will only accelerate -- with Apple leading the way.