John Paczkowski on the reasoning behind Apple using their own mapping service in iOS 6:
Spoken turn-by-turn navigation has been a free service offered through Google’s Android mobile OS for a few years now. But it was never part of the deal that brought Google’s Maps to iOS. And sources say Apple very much wanted it to be. Requiring iPhone users to look directly at handsets for directions and manually move through each step — while Android users enjoyed native voice-guided instructions — put Apple at a clear disadvantage in the mobile space. And having chosen Google as its original mapping partner, the iPhone maker was now in a position where an archrival was calling the shots on functionality important to the iOS maps feature set.
And this caused Apple — which typically enjoys very tight control over its products — no end of philosophical discomfort, sources say. Apple pushed Google hard to provide the data it needed to bring voice-guided navigation to iOS. But according to people familiar with Google’s thinking, the search giant, which had invested massive sums in creating that data and views it as a key feature of Android, wasn’t willing to simply hand it over to a competing platform.