Genuinely, it's not Google nor Apple that I fear doing something evil here.
Google will try to give me more targeted ads, without giving that detailed data to their app developers, but instead just making their demographics tools better.
Apple will do what they think will help the circumstance.
I fear the government doing evil with it, especially under the guise of good.
"Hey, we found this terrorist's phone number, turns out he has an Android device. Give me every person that's been physically near him in the last 24 hours"
"Hey, these 37 people were at a protest, where do they spend their off time?"
Well, sure; if it didn't have walls, it wouldn't be a castle.
Some castles rely entirely on their own walls
And then they'll do it anyway a few years later, when you're not looking. Just look at Google's introduction and continuous tightening of SafetyNet requirements.
And what the hell can you do? Switch to buying Apple, who set the gold standard for this crap years ago? Switch to Purism, which BankID (practically mandatory for life in Sweden, sadly) still hasn't been ported to?
You get a chance and you take it. All things bring you towards success one step at a time, as unsatisfying as it might feel.
Even if Google or Apple are _capable_ of doing something evil, you can stil prevent them from excersing that power by not setting an example that it's okay to do so.