What is side-loading?
Side-loading is simply downloading apps from outside of the app store it has been common practice to do so on android via its package manager APK.
What are APK'S
Android package kit or apks is androids package file and method of installing apps from alternative sources say Epic games for example not available on the play store but can be downloaded via epics website selecting download and then apk which then enables you to download and install the fortnite app
IS side-loading safe?
On newer versions of android google makes you decide whether a program can install apks and may warn you of the safety of installing one however basic vigilance online can prevent any virus/malware issues take net-mirror for example which cannot be downloaded from the play store but is completely safe to use however if a file upon initiating the install has a blank name or has strange characters it is a warning sign that the file is bad and should be deletedÂ