How to install apk from Unknown sources

How to enable the installation of apk. From your smartphone you will have to access the Settings, find the entry for the Safety and then enable the voice Unknown origins. As you may have understood, therefore, the steps are very few and simple, but it is important to clarify that in this way you will give space to any apk file to install itself smartphone. So always pay a lot of attention to what you install.

How to enable apk installation: 1. Look for "Security" in the settings
How to enable apk installation: 2. Enable Unknown sources