Do you consider using an antivirus and anti-malware ? Indeed a Free apps store may be compromized. I am personnaly happy with Sophos Intercept X for mobile. i also use opendns as static dns. Any advices or opinion ?
I have never read anything that convinced me that anti-virus software in needed or desirable on an Android mobile phone (or any other phone come to that). Most of the things I have read that made that argument were written by people with some form of vested interest in such software.
Don’t click on dodgy links, don’t open unexpected attachments, don’t install apps from sources you don’t trust, and you wont go far wrong (in my humble opinion of course )