Never Install Unofficial Apps: Regardless of whether it’s Android, iOS, or any other platform you’re using, it’s not advisable to install unofficial apps. But, Android users tend to do it, at alarming rates. Well, if you don’t know what an unofficial app is, basically, every app download from any source other than Play Store, is an unofficial application. Usually, such apps carry harmful elements with them, such as, malware, ransomware, and many others, which are then used by hackers to exploit your device.