Any Android device by default does not allow apps to be installed from untrusted developer or sources for security reason. Even if you get an app transferred from your friends or colleagues device cannot be installed without enabling the settings on your device.
As mentioned above, when you click on install from the Google playstore the app gets installed to your Android device without any interaction required. Except after installing you will have to provide required access for the apps. Here I am letting you know how to install Android app from untrusted developer.
So how to install from untrusted developer?
Once the app is downloaded from any website or got it transferred from your friends. Follow the below steps to install it.
- Tap on Settings >> Security
- Tap on Device Administration or Install unknown apps
- Turn on “Unknown Sources”
Once the necessary changes are done in the settings, use any file manager app to access the APK file downloaded.
Tap on the APK file to install
You will get an pop-up, tap on install.
After installing the app, now navigate to the main menu to access the app and start using it.