Apple Maps UI: A big map, with a search bar at the bottom. Simple and nothing but the essentials.
Google Maps UI: A page full of ads, a map full of ads and ads masquerading as recommendations. Plus five tab bar buttons at the bottom to not accomplish very much.
I've switched to Apple Maps simply because of its better UX and how much easier the app is to use. As far as I can tell, their mapping and navigational data in Canada is every bit as good as Google's. The only thing keeping Google Maps on my phone is their superior reviews. Once Apple replaces Yelp reviews, I'll jettison the Google Maps app into the sun.