As soon as somebody says an operating system is virus-proof, another person tries to write a virus for it immediately. Viruses are still a very real possibility even if you just download from the official Google or Apple app stores.
Finally, many antivirus apps are available to scan each app that comes through crook means. One of such on the mobile platform is the Lookout Security and Antivirus. It is available for free on iOS and Android and remains one of the highest ranked antivirus apps. Additional features are unlocked for a fee.
First: Biometric Scanning Hardware
Other Ways to Secure your Smartphone: