You can’t always trust what you download, even on official app marketplaces like the Google Play Store. An app called System Update has been taken down by Google because it was actually spyware. Unfortunately, it has already been downloaded millions of times in the past. The spyware was discovered by security firm Zscaler and alerted Google about its existence. The app was launched back in 2014 and it sent data about a device’s location to whomever created the app. It was also able to look at certain incoming text messages. According to Zscaler, if you installed and tried to use System Update, it’ll look like it stopped working and display the message “Unfortunately, Update Service has stopped.” But it’ll actually still work in the background.
The app’s Play Store page was actually telling of how fake it was. There were no screenshots there nor a proper description of the app. It had negative reviews as well. From your end, make sure you scrutinize the new apps you plan to download to your devices.
Source: Android Authority