“The criminals have gotten really good at making these look very official, very slick, very well defined,” said Alex Hamerstone of security company TrustedSec. “It might even be a very fun game. But things often times might be simpler, a calculator app or a flashlight app that is pretty easy to code.” Hamsterstone said those fake flashlight or calculator apps can constantly run on your phone, and when you log into your banking app the Trojan app steals your account information.