Android is much more functional, just look at how much more functional widgets are. But one of the reasons I stay with Apple is because I feel like they value my privacy, where Google just wants every shred of every detail of my life in order to make money off of it. I know it's a terrible reason in today's world of zilch privacy, but I just cant ever get over the feeling of someone looking over my shoulder when using an Android phone.
Respectable reason, but it doesn't work like that. Just read the fine print on both sides.
Apple has your data, and claims to protect it, and only use it to better their products. Fair enough.
Google does that same, but also uses it to further your search engine, products, etc.
Your data may be used by google, but it isn't something to "look over your shoulder" about. Its more like this: Imagine all the smartphone users in the world are jelly beans. Google takes all those jelly beans and fills the grand canyon with them. Google then uses its algorithms to analyze said jelly beans in mass. What color are they? How big are they? How many of each color? Etc, etc. Each individual jelly bean is essentially autonomous, and impossible to single out. Google takes the data from the mass trends to further its own goals.
If you want to avoid this, you should stop using all google services, etc....not to mention other companies.
The only time it really matters, is if the authorities want your data. At that point, it is up to the individual companies how are they will go to protect your data. But that is a different situation, and doesn't amount to be paranoid about using your phone.
Another way to put it (with no offense intended), you are not that special. I am not that special. They care about the data of the masses, not my individual habits. The data mining does serve to better my experience, though.
Advertising is a separate matter, and not just a google thing. You can prevent personal advertisements on both platforms.