What Could Cause a Black Dot on My Dad’s Phone Screen?

Definitely not a virus! More likely, the screen is damaged. I had a similar issue with my phone before, and it turned out to be a hardware problem.

A black dot typically indicates a hardware issue rather than malware. In normal cases, viruses don’t announce their presence like that.

Could be a dead pixel! I've had that happen, and Apple replaced my phone for a similar issue, so it's worth getting checked.

It sounds like your dad's phone has a damaged screen rather than a virus. Viruses typically don’t show obvious signs like that, so I’d look into a repair instead.

I agree, that’s likely just screen damage. Viruses usually don’t cause visible issues. You might want to check for dead pixels or get it looked at.