At home, I use the free version of Avast and I use it on my mobile devices as well. I also use the free version of AVG on my mobile devices. Knock on wood, I've been virus free for forever. I'll also do a scan with Malware Bytes now and then.
I also use Firefox with NoScript and AdBlock Plus. Yesterday, though, I read an article that says that NoScript is possibly subject to malware and that Firefox patches are on the way.
Here at work, I have no control over the system so I trust that they know what they're doing.