Over half a million Google Android users have downloaded a set of driving apps with absolutely no legitimate functions.

According to ESET security researcher Lukas Stefanko, the apps, published by a developer under the name Luiz O Pinto, account for at least 560,000 installs.

There are 13 applications in total, all of which relate to driving simulation in some way.

The Android apps include a truck cargo simulator, luxury car driving, motocross, and fire truck simulations, some of which displayed with very similar graphics to alternative, legitimate applications.

Once installed, the apps demonstrate no legitimate functionality. Instead, the apps hide themselves and their shortcut icons, requesting that the user download and install an additional .APK at the same time.

If consent is granted, the app then displays ads without permission when the mobile device is unlocked. Some previous users have reported that the apps also caused severe device slowdown.

The apps were reported and at the time of writing, appear to have been removed from the Google Play Store.

ZDNet