While there are a number of free virus scanners from more or less well-known manufacturers even in the Appstores of Apple or Google to load the good protection promise, but often they fail in the simple tests already miserable, or even open in the worst case, additional vulnerabilities, which has definitely saved you in the wrong place.
Because really nothing is free in life. Even free antivirus software has a price that you often have to pay at least in the form of annoying advertising.
An exception that achieves quite acceptable results is AVG’s antivirus software. However, you have to accept here also in the free version always cuts in the quality and scope of service.
Today, almost all well-known manufacturers offer good to very good complete packages for several devices, with which you can partially secure up to 10 devices. As a result, you will buy a good antivirus software, and thus have several PCs, smartphones, tablets and notebooks in the bag, instead of having to purchase a separate software where you pay more in the end than for a complete solution.