What always surprises me is the sheer amount of fake, scammy, apps trying to appear as if they're something else. Trying to steal clicks from users looking for Adblock, VLC or other legitimate apps... it's a mess!
When you select an app to install on Google Play, it takes you to another screen confirming the install. But that install button on top is not for the app you selected, it's for a different, advertised app. You have to scroll down to find the confirmation button for the app you already instructed the store to install.
This isn't going to ruin any lives, but it's gross.
I don't need alternative app stores to download malware and scams, that play store is full of that. And it's advertised front and center.
You're competing with Google. The built-in Drive app does document scanning.