It’s a Chinese app that lets people “scan” a document using the camera on their phone. It was “free” for a long time, turns out it was dropping injected adware on people’s phones.
To be honest, Microsoft lens has had the same features for a long time, but didn’t have “scanner” in the name and most app searches are piss poor so people just literally searched “camera scanner” and got the adware result. Microsoft has their own long and shady history, but dropping an adware payload wasnt part of that.