Known as the Joker virus that attacks Android devices hides within many apps one can download from Google Play Store. You won't know it because it is stealthy. Its danger is that once installed the malware is capable of subscribing the user to payment services without authorization. Unless you constantly check your bank account, you would not even notice.
This malware first appeared in 2017 and since then has forced Google to remove 1700 apps with the malware from their Google store. However, in the Fall of 2020, it was found in 24 Android apps that had a total of 500,000 downloads before being discovered and removed. It had affected over 30 countries including the USA. The malware subscribes to an online service and will only take $7 weekly from your account but this will gradually increase more and more over time. Android cell phones are the only ones subject to this malware.
Once infected, the malware can access all kinds of information on the device and subscribe the owner to services without their knowledge or approval. The malware is able to verify the device used to the service but not the user allowing the payment without any user interaction! Unless the user is checking their bank accounts and notices unknown charges, the account will continued to be drained. The bank of the user does not notice anything wrong because the amounts are small and it looks like a normal subscription service.
Google is constantly checking their available apps that can be downloaded but they continue to be a problem.