The time difference between the iPod announcement and general availability was a negligible 18 days (10/23/01-11/10/01). With Google, you chose to use the Nov 5, 2007 announcement of the Open Handset Alliance as your 'since Android' starting point, even though the first device built on Android was the HTC Dream, released the following year on October 22, 2008 (352 days). The truth of the matter is that comparing the charts is of dubious value since all three charts you're covering are of different timespans. Your Apple chart is a decade long (I'm not sure why you measured since the launch of the iPod instead of the iPhone or iPad), and in all three cases the majority of the chart represents a time period when the product in question (iPod, Kindle and Android) were inconsequential parts of the company revenue. I like your ideas about offensive vs defensive products, but it's misleading to put big charts with percentage gains or losses based on cherry-picked start times and call it evidence to support your position.