I just installed Protonmail on my Android device, and I was wondering how much data can Android (Google, really) can get from my use of that app, or from any app in general for that matter. I write this post with a faint level of paranoia, as you can guess - with all the mail scanning that gmail does to get data on you, one can tend to think that anything entered or typed on a Google-powered platform is being analyzed, be it Gmail or Android. But of course, I'm assuming it must not be that simple or even that bad. The problem is that getting actual data on what is going on can be quite cryptic.
So, what can Google really get from my use of any given app? Can they somehow "see" what I type in my Proton mails (I'm not thinking about keylogging, that would be illegal), do they collect any kind of metadata that are a bit too comprehensive, etc?