A few days ago I wrote a short blog post about how to prevent email spoofing of your domain.
Suddenly I started seeing hundreds of visitors with the referrer android-app://com.google.android.googlequicksearchbox/https/www.google.com. I had no idea what that means, but I assumed it had something to do with Google Search on mobile. I did remember that they promote blog posts on the Google search homepage sometimes, so I think mine was featured there for some reason.
Today, I logged into my search console and it was actually confirmed that the traffic came from "Discover".

Google says I got 1433 clicks, my own analytics app says 1505 unique visits came from that android-app source.
I just wrote this blog post because I recently encountered this problem and didn'd find a TL;DR on how to solve it, I didn't expect any traffic from it. I just wanted to help others in the same situation.
Fun fact: looking at the stats, out of those 1500 users, 14 checked out my pricing page and one even clicked the buy button, but never purchased.
That's awesome! How long has your site/blog been live overall?
A few weeks, but I didn't have any articles on it. This is actually the first real blog post, there is another one but it's just the instructions to install userTrack on WordPress.
Pretty empty: https://usertrack.net/blog