Do we need antivirus in Galaxy S Advance?????????
No, you don't need antivirus apps for android in general. As long as you download apps from reputable sources like the play store you will be fine.
Google automatically scans apps for malicious code.
Probably not - but if you can get get a reputable free one why not? Will maybe have some effect on your battery drain.
Of more concern are the permissions that different apps demand. I recently had an update for one app which seemed to be primarily to allow the app to access my contact list - I promptly deleted the app. This was one of the Open Office apps from the Google Store - why it could possibly need my contact list details is something to speculate about!!!
Did you read the what's new section where apps generally tell you why they need new things?
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