An Android app is a single file with the '.apk' extension also known as APK.
When installing an app from your official store you don't see the file because all the processes (download and install) are managed by the Android operating system.
In some cases, like unofficial downloads or downloads from stores different from the phone default one, you may have to install the APK manually.
This tutorial will explain how to do that.
I suggest to download the APK to your computer and check it with an antivirus before install.
Apps downloaded from my pages are safe as they are the same uploaded to Google Play app store.
If the APK comes in a zipped archive, unzip it on the PC.
Transferring the file to the device is quite simple: choose from Bluetooth or usb cable.
USB: connect the device to the PC and choose a folder on it or create a new one. Drag and drop the APK from the PC to that folder.
I suggest to use the 'download' folder if exist (see image).
Once the APK is on the device follow these simple steps to complete the installation:
Complete the installation: Press the Back key to go back to the installation window and click Install.
If closing the Security window will not bring you back to the app installation use the file manager to start it again.
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