I use Avast on all my devices - desktop, laptops, tablets, and smart-phone. It does the job very well, but doesn't get in the way of processor or network performance. It has active elements (as well as a scan function) that prevent you from getting a virus or malware to begin with, rather than JUST an after-the-fact scanner that tells you that you aleady have one. If you have a smart-phone, it has a browser that can go to the same places that can give a virus to a computer, and some of the more dreaded of those viruses and malware can also infest Android and/or iOS systems. With so many people doing their shopping, banking, investing, etc from their tablets and phones these days, the hackers are not about to let that lucrative "market" slip by them untapped. Yay or nay? To each his own, but I'd rather be safe than sorry on this one. Besides, it doesn't cost me a thing. I use the freeware version of Avast on all my devices.