Android is an open-source mobile device operating system that was created by Google. The latest version of Android is 9.0 Pie, which was released in 2018.
Today, Android is one of the most used mobile operating systems along with iOS. Because of this, hackers often create malware for Android because of its larger market share. Viruses on Android are usually fake programs on Google Play. Android also has some ransomware viruses, but these function very differently than ransomware on PCs. The malware is usually wiped by Google shortly after the discovery. Because of Android's operating system, and ease of us, it is very easy to create fake apps as Android allows users to download programs with little to no security or authenticity check. Unlike iOS, apps can be developed and put on the Play Store for just $5 and without in-depth security checks. While IOS requires a full malware check and a 100$ fee before posting, this fee and security check makes it expensive and incredibly difficult to post infected apps in the app store.
Android also allows the user to give administrative permissions to apps. This means that infected apps can gain permission to everything on the phone, including external hardware. There is certain administrative permissions that can be granted, including access to use microphones, cameras and internal monitors such as gyroscopes, accelerometers, and GPS, being one. Hackers however, would rather use these to Control the screen and overwriting app displays, and grabbing system information such as Wi-Fi, Bluetooth, Operating system information and CPU or graphics usage.
If the developer of an app is banned from using the Play Console, they can make an APK (short for Android Package Installer, which is a Android installer file that can be installed from sources other than the Google Play Store) which can contain the malware. This can be made with Android Studio, officially from Google.