I always had a Nokia with Windows. I didn't Need antivirus.
Now, with Nokia 5 with Android, I have to install an antivirus? Which? (AVG, AVIRA, ecc.).
You don't need an antivirus on Android. Just remember to only download apps from reputable sources (e.g. Play Store, Amazon App Store, APKMirror), use an ad-blocker to get rid of unwanted advertisements and install security updates when they are available.
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