'Phone Update Recommended' Pop-Up Scam
A new online scam is targeting users who are browsing the Internet on their mobile devices. This specific scam is focused on users who have Android phones and tablets.
The scam is being pushed through misleading and untrustworthy websites that display it in the form of a pop-up. Of course, the pop-up only shows up for users landing on those misleading pages while using a mobile browser and an Android device.
The scam is contained in a pop-up window that tells the victim that their device is suffering from poor processor and memory performance and needs fixing. The same pop-up tells the user they need to download a nondescript "Android antivirus" for free from the Play Store. Of course, the scam and its authors have nothing to do with the legitimate Google Play Store.
The button in the pop-up will open an arbitrary location, as set by the scam's authors. This could be any hostile page or malicious file.
Remember that any page that gives you any sort of scary information about your device, whether it's your phone or personal computer, is lying to you as it cannot have access to this sort of information in the first place. Just close all similar warnings and move on.