I think that the default for collecting any kind of personal data should be opt-in consent.
Al FrankenGoogle's screen for privacy settings does give you more options for what you share than Apple's does. But it's not a complete list, and people aren't aware of whether or not that information will go to a third party.
Al FrankenHe [Newt Gingrich] is the most unpopular politician in America. His favorable rating is only four points higher than the Unabomber.
Al Franken