Attention Android users! Beware of third-party app stores outside of Google Play. Smartphone security company Lookout warns that these stores are rife with duplicate versions of popular apps "including Candy Crush, Facebook, GoogleNow, NYTimes, Okta, Snapchat, Twitter, WhatsApp, and many others". These duplicates are often fully functioning so the user won't be able to tell the difference, but there is one: they contain malware that embeds itself as a system application and is almost impossible to remove.

Lookout says there are more than 20,000 of these apps out there, adding that “victims will likely not be able to uninstall the malware, leaving them with the options of either seeking out professional help to remove it, or simply purchasing a new device”. Uninstalling the app or even bringing the phone back to factory settings won’t help.

blog.lookout.com/blog/2015/11/04/trojanized-adware