Now, there's a new ransomware going around that targets Android gadgets. Right now, "Koler" is looking for devices to infect, and it follows a familiar script.
It's known as a "policeware" or "police locker," and it takes over your Android and warns that you're under surveillance by federal agents. It says you're suspected of criminal activity - viewing illegal pornography, in this case. It demands a ransom of $300, paid via MoneyPak, to unlock your phone.
The malware doesn't get on your Android out of the blue. You have to enable it, by being fooled into installing a special "video player" app. The app isn't in Google Play Store, so you're safe if you don't have "Allow installation of apps from unknown sources" enabled in your security settings.