I think OS marketshare still doesn't matter that much to Apple.
Let's take this pumpkin pie.
Apple gets a slice that is 17% of the pie. Pretty big slice. Then there a few slivers that go to other people. Then 74% goes to Android manufacturers.
That means Motorola, Samsung, LG, HTC, Sony, Huawei, ZTE, Kyocera, Oppo, Lenovo... and countless other Chinese manufacturers... have to share 74% of that pie.
Seems like Apple is eating the best here.
Not to mention that all of Apple's phones come at a premium price which net's them higher profit margin than most others. A huge chunk of Android market share can be attributed to low end smartphones sold in emerging markets. India and China come to mind. Also... most of that 74% is running older Android software... Gingerbread, ICS... etc.