Is there any type of malware that can change search history, specifically for Android phones?

Sometimes, my dad will let me use his phone and I found in his search history some very disturbing things like pornography. I am really scared around him now, and I don't know if it is a virus or not. So, is this him searching these, or is it some type of malware/spyware? Thank you.
Asked May 10, 2014

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